diff --git a/examples/Azure_IoT_Central_ESP32/AzureIoT.cpp b/examples/Azure_IoT_Central_ESP32/AzureIoT.cpp
index 6b5b5a0..dbe7320 100644
--- a/examples/Azure_IoT_Central_ESP32/AzureIoT.cpp
+++ b/examples/Azure_IoT_Central_ESP32/AzureIoT.cpp
@@ -15,8 +15,8 @@
 log_function_t default_logging_function = NULL;
 #endif // DISABLE_LOGGING
 
-/* --- Azure Abstractions --- */
-#define IOT_HUB_MQTT_PORT                           8883
+/* --- Azure Definitions --- */
+#define IOT_HUB_MQTT_PORT                           AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
 #define MQTT_PROTOCOL_PREFIX                        "mqtts://"
 #define DPS_GLOBAL_ENDPOINT_MQTT_URI                MQTT_PROTOCOL_PREFIX DPS_GLOBAL_ENDPOINT_FQDN
 #define DPS_GLOBAL_ENDPOINT_MQTT_URI_WITH_PORT      DPS_GLOBAL_ENDPOINT_MQTT_URI ":" STR(DPS_GLOBAL_ENDPOINT_PORT)
@@ -45,6 +45,8 @@ log_function_t default_logging_function = NULL;
 #define EXIT_IF_AZ_FAILED(azresult, retcode, message, ...)                          \
   EXIT_IF_TRUE(az_result_failed(azresult), retcode, message, ##__VA_ARGS__ )
 
+#define NUMBER_OF_SECONDS_IN_A_MINUTE               60
+
 /* --- Internal function prototypes --- */
 static uint32_t get_current_unix_time();
 
@@ -71,17 +73,17 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
 static az_span generate_dps_register_custom_property(az_span model_id, az_span data_buffer, az_span* remainder);
 
 #define is_device_provisioned(azure_iot) \
-  (!az_span_is_empty(azure_iot->config->iot_hub_fqdn) && !az_span_is_empty(azure_iot->config->device_id))
+  (!is_az_span_empty(azure_iot->config->iot_hub_fqdn) && !is_az_span_empty(azure_iot->config->device_id))
 
 /* --- Public API --- */
-int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
+void azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
 {
   _az_PRECONDITION_NOT_NULL(azure_iot);
   _az_PRECONDITION_NOT_NULL(azure_iot_config);
   if (azure_iot_config->use_device_provisioning)
   {
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->iot_hub_fqdn));
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->device_id));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->iot_hub_fqdn));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->device_id));
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->dps_id_scope, 1, false);
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->dps_registration_id, 1, false);
   }
@@ -89,14 +91,14 @@ int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
   {
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->iot_hub_fqdn, 1, false);
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->device_id, 1, false);
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->dps_id_scope));
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->dps_registration_id));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->dps_id_scope));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->dps_registration_id));
   }
   _az_PRECONDITION_VALID_SPAN(azure_iot_config->device_key, 1, false);
   _az_PRECONDITION_VALID_SPAN(azure_iot_config->data_buffer, 1, false);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.base64_decode);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.base64_encode);
-  _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.hmac_sha512_encrypt);
+  _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.hmac_sha256_encrypt);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_init);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_deinit);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_subscribe);
@@ -115,8 +117,6 @@ int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
   {
     azure_iot->config->sas_token_lifetime_in_minutes = DEFAULT_SAS_TOKEN_LIFETIME_IN_MINUTES;
   }
-
-  return RESULT_OK;
 }
 
 int azure_iot_start(azure_iot_t* azure_iot)
@@ -237,7 +237,8 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
   size_t length;
   mqtt_client_config_t mqtt_client_config;
   mqtt_message_t mqtt_message;
-  az_span data_buffer, dps_register_custom_property;
+  az_span data_buffer;
+  az_span dps_register_custom_property;
       
   switch (azure_iot->state)
   {
@@ -250,7 +251,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         // This seems harmless, but...
         // azure_iot->config->data_buffer always points to the original buffer provided by the user.
-        // azure_iot->data_buffer is an intermediate pointer. It starts by pointint to azure_iot->config->data_buffer.
+        // azure_iot->data_buffer is an intermediate pointer. It starts by pointing to azure_iot->config->data_buffer.
         // In the steps below the code might need to retain part of azure_iot->data_buffer for saving some critical information,
         // namely the DPS operation id, the provisioned IoT Hub FQDN and provisioned Device ID (if provisioning is being used).
         // In these cases, azure_iot->data_buffer will then point to `the remaining available space` of azure_iot->config->data_buffer
@@ -277,6 +278,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed initializing MQTT client.");
+        return;
       }
 
       break;
@@ -287,15 +289,15 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       azure_iot->state = azure_iot_state_subscribing_to_dps;
 
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, 
-          (const uint8_t*)AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC),
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC),
           mqtt_qos_at_most_once);
           
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed subscribing to Azure Device Provisioning respose topic.");
+        return;
       }
 
       break;
@@ -314,19 +316,19 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
         return;
       }
 
-      mqtt_message.topic = az_span_split(data_buffer, length, &data_buffer);
+      mqtt_message.topic = split_az_span(data_buffer, length, &data_buffer);
 
-      if (az_span_is_empty(mqtt_message.topic) || az_span_is_empty(data_buffer))
+      if (is_az_span_empty(mqtt_message.topic) || is_az_span_empty(data_buffer))
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed allocating memory for DPS register payload.");
+        LogError("Failed reserving memory for DPS register payload.");
         return;
       }
 
       dps_register_custom_property = generate_dps_register_custom_property(
         azure_iot->config->model_id, data_buffer, &mqtt_message.payload);
 
-      if (az_span_is_empty(dps_register_custom_property))
+      if (is_az_span_empty(dps_register_custom_property))
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed generating DPS register custom property payload.");
@@ -359,6 +361,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed publishing to DPS registration topic");
+        return;
       }
 
       break;
@@ -405,6 +408,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed publishing to DPS status query topic");
+        return;
       }
 
       break;
@@ -437,7 +441,8 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       if (azure_iot->config->mqtt_client_interface.mqtt_client_init(&mqtt_client_config, &azure_iot->mqtt_client_handle) != 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed initializing MQTT client.");
+        LogError("Failed initializing MQTT client for IoT Hub connection.");
+        return;
       }
 
       break;
@@ -447,13 +452,15 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       azure_iot->state = azure_iot_state_subscribing_to_pnp_cmds;
       
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC),
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play commands topic.");
+        LogError("Failed subscribing to IoT Plug and Play commands topic.");
+        return;
       }
 
       break;
@@ -463,30 +470,33 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       azure_iot->state = azure_iot_state_subscribing_to_pnp_props;
 
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC, 
-          lengthof(AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle, 
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC), 
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play properties topic.");
+        LogError("Failed subscribing to IoT Plug and Play properties topic.");
+        return;
       }
-    
-      break;
 
+      break;
     case azure_iot_state_subscribing_to_pnp_props:
       break;
     case azure_iot_state_subscribed_to_pnp_props:
       azure_iot->state = azure_iot_state_subscribing_to_pnp_writable_props;
     
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC),
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play writable properties topic.");
+        LogError("Failed subscribing to IoT Plug and Play writable properties topic.");
+        return;
       }
 
       break;
@@ -501,13 +511,14 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
         azure_iot->state = azure_iot_state_error;
         LogError("Failed getting current time for checking SAS token expiration.");
       }
-      else if ((azure_iot->sas_token_expiration_time - now) < SAS_TOKEN_REFRESH_THRESHOLD_SECS)
+      else if ((azure_iot->sas_token_expiration_time - now) < SAS_TOKEN_REFRESH_THRESHOLD_IN_SECS)
       {
         azure_iot->state = azure_iot_state_refreshing_sas;
         if (azure_iot->config->mqtt_client_interface.mqtt_client_deinit(&azure_iot->mqtt_client_handle) != 0)
         {
           azure_iot->state = azure_iot_state_error;
           LogError("Failed de-initializing MQTT client.");
+          return;
         }
       }
       break;
@@ -559,7 +570,7 @@ int azure_iot_send_properties_update(azure_iot_t* azure_iot, uint32_t request_id
 
   azr = az_iot_hub_client_properties_get_reported_publish_topic(
       &azure_iot->iot_hub_client, request_id_span, (char*)az_span_ptr(data_buffer), az_span_size(data_buffer), &topic_length);
-  EXIT_IF_AZ_FAILED(azr, RESULT_ERROR, "Failed to get the repoted properties publish topic");
+  EXIT_IF_AZ_FAILED(azr, RESULT_ERROR, "Failed to get the reported properties publish topic");
 
   mqtt_message.topic = az_span_slice(data_buffer, 0, topic_length);
   mqtt_message.payload = message;
@@ -690,7 +701,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
   {
     // This message should either be:
     // - a response to a properties update request, or
-    // - a response to a get properties request, or
+    // - a response to a "get" properties request, or
     // - a command request.
 
     az_iot_hub_client_properties_message property_message;
@@ -725,7 +736,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
             
             if (az_result_failed(az_span_atou32(property_message.request_id, &request_id)))
             {
-              LogError("Failed parsing properties update request id (%.*s)", 
+              LogError("Failed parsing properties update request id (%.*s).", 
                 az_span_size(property_message.request_id), az_span_ptr(property_message.request_id));
               result = RESULT_ERROR;
             }
@@ -789,14 +800,14 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
       {
         result = RESULT_OK;
 
-        if (az_span_is_empty(azure_iot->dps_operation_id))
+        if (is_az_span_empty(azure_iot->dps_operation_id))
         {
-          azure_iot->dps_operation_id = az_span_slice_and_copy(azure_iot->data_buffer, register_response.operation_id, &azure_iot->data_buffer);
+          azure_iot->dps_operation_id = slice_and_copy_az_span(azure_iot->data_buffer, register_response.operation_id, &azure_iot->data_buffer);
 
-          if (az_span_is_empty(azure_iot->dps_operation_id))
+          if (is_az_span_empty(azure_iot->dps_operation_id))
           {
             azure_iot->state = azure_iot_state_error;
-            LogError("Failed allocating memory for DPS operation id.");
+            LogError("Failed reserving memory for DPS operation id.");
             result = RESULT_ERROR;
           }
         }
@@ -812,9 +823,9 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
         az_span data_buffer = azure_iot->config->data_buffer; // Operation ID is no longer needed.
         azure_iot->data_buffer = data_buffer; // In case any step below fails.
 
-        azure_iot->config->iot_hub_fqdn = az_span_slice_and_copy(data_buffer, register_response.registration_state.assigned_hub_hostname, &data_buffer);
+        azure_iot->config->iot_hub_fqdn = slice_and_copy_az_span(data_buffer, register_response.registration_state.assigned_hub_hostname, &data_buffer);
         
-        if (az_span_is_empty(azure_iot->config->iot_hub_fqdn))
+        if (is_az_span_empty(azure_iot->config->iot_hub_fqdn))
         {
           azure_iot->state = azure_iot_state_error;
           LogError("Failed saving IoT Hub fqdn from provisioning.");
@@ -822,9 +833,9 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
         }
         else
         {
-          azure_iot->config->device_id = az_span_slice_and_copy(data_buffer, register_response.registration_state.device_id, &data_buffer);
+          azure_iot->config->device_id = slice_and_copy_az_span(data_buffer, register_response.registration_state.device_id, &data_buffer);
                     
-          if (az_span_is_empty(azure_iot->config->device_id))
+          if (is_az_span_empty(azure_iot->config->device_id))
           {
             azure_iot->state = azure_iot_state_error;
             LogError("Failed saving device id from provisioning.");
@@ -848,7 +859,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
   }
   else
   {
-    LogError("No PUBLISH notification expected");
+    LogError("No PUBLISH notification expected.");
     result = RESULT_ERROR;
   }
   
@@ -870,7 +881,7 @@ int azure_iot_send_command_response(azure_iot_t* azure_iot, az_span request_id,
   azrc = az_iot_hub_client_commands_response_get_publish_topic(
       &azure_iot->iot_hub_client, request_id, response_status, 
       (char*)az_span_ptr(mqtt_message.topic), az_span_size(mqtt_message.topic), &topic_length);
-  EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed to get the commands response topic");
+  EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed to get the commands response topic.");
 
   mqtt_message.topic = az_span_slice(mqtt_message.topic, 0, topic_length);
   mqtt_message.payload = payload;
@@ -903,7 +914,7 @@ static uint32_t get_current_unix_time()
 }
 
 /*
- * @brief           Initializes the Device Provisioning client and generates the config for a MQTT client.
+ * @brief           Initializes the Device Provisioning client and generates the config for an MQTT client.
  * @param[in]       azure_iot          A pointer to an initialized instance of azure_iot_t.
  * @param[in]       mqtt_client_config A pointer to a generic structure to contain the configuration for
  *                                     creating and connecting an MQTT client to Azure Device Provisioning service.
@@ -912,8 +923,13 @@ static uint32_t get_current_unix_time()
  */
 static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_config_t* mqtt_client_config)
 {
-  az_span data_buffer_span, client_id_span, username_span, password_span;
-  size_t client_id_length, username_length, password_length;
+  az_span data_buffer_span;
+  az_span client_id_span;
+  az_span username_span;
+  az_span password_span;
+  size_t client_id_length;
+  size_t username_length;
+  size_t password_length;
   az_result azrc;
 
   azrc = az_iot_provisioning_client_init(
@@ -926,8 +942,8 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
 
   data_buffer_span = azure_iot->data_buffer;
   
-  password_span = az_span_split(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(password_span), RESULT_ERROR, "Failed allocating buffer for password_span.");
+  password_span = split_az_span(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(password_span), RESULT_ERROR, "Failed reserving buffer for password_span.");
 
   password_length = generate_sas_token_for_dps(
     &azure_iot->dps_client,
@@ -939,14 +955,14 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
     &azure_iot->sas_token_expiration_time);
   EXIT_IF_TRUE(password_length == 0, RESULT_ERROR, "Failed creating mqtt password for DPS connection.");    
 
-  client_id_span = az_span_split(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(client_id_span), RESULT_ERROR, "Failed allocating buffer for client_id_span.");
+  client_id_span = split_az_span(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(client_id_span), RESULT_ERROR, "Failed reserving buffer for client_id_span.");
 
   azrc = az_iot_provisioning_client_get_client_id(
       &azure_iot->dps_client, (char*)az_span_ptr(client_id_span), az_span_size(client_id_span), &client_id_length);
   EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed getting client id for DPS connection.");
 
-  username_span = az_span_split(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
+  username_span = split_az_span(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
 
   azrc = az_iot_provisioning_client_get_user_name(
       &azure_iot->dps_client, (char*)az_span_ptr(username_span), az_span_size(username_span), &username_length);
@@ -963,7 +979,7 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
 }
 
 /*
- * @brief           Initializes the Azure IoT Hub client and generates the config for a MQTT client.
+ * @brief           Initializes the Azure IoT Hub client and generates the config for an MQTT client.
  * @param[in]       azure_iot          A pointer to an initialized instance of azure_iot_t.
  * @param[in]       mqtt_client_config A pointer to a generic structure to contain the configuration for
  *                                     creating and connecting an MQTT client to Azure IoT Hub.
@@ -972,8 +988,13 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
  */
 static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_client_config_t* mqtt_client_config)
 {
-  az_span data_buffer_span, client_id_span, username_span, password_span;
-  size_t client_id_length, username_length, password_length;
+  az_span data_buffer_span;
+  az_span client_id_span;
+  az_span username_span;
+  az_span password_span;
+  size_t client_id_length;
+  size_t username_length;
+  size_t password_length;
   az_result azrc;
 
   azure_iot->iot_hub_client_options = az_iot_hub_client_options_default();
@@ -989,8 +1010,8 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
 
   data_buffer_span = azure_iot->data_buffer;
   
-  password_span = az_span_split(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(password_span), RESULT_ERROR, "Failed allocating buffer for password_span.");
+  password_span = split_az_span(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(password_span), RESULT_ERROR, "Failed reserving buffer for password_span.");
 
   password_length = generate_sas_token_for_iot_hub(
     &azure_iot->iot_hub_client,
@@ -1002,14 +1023,14 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
     &azure_iot->sas_token_expiration_time);
   EXIT_IF_TRUE(password_length == 0, RESULT_ERROR, "Failed creating mqtt password for IoT Hub connection.");    
 
-  client_id_span = az_span_split(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(client_id_span), RESULT_ERROR, "Failed allocating buffer for client_id_span.");
+  client_id_span = split_az_span(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(client_id_span), RESULT_ERROR, "Failed reserving buffer for client_id_span.");
 
   azrc = az_iot_hub_client_get_client_id(
       &azure_iot->iot_hub_client, (char*)az_span_ptr(client_id_span), az_span_size(client_id_span), &client_id_length);
   EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed getting client id for IoT Hub connection.");
 
-  username_span = az_span_split(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
+  username_span = split_az_span(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
 
   azrc = az_iot_hub_client_get_user_name(
       &azure_iot->iot_hub_client, (char*)az_span_ptr(username_span), az_span_size(username_span), &username_length);
@@ -1064,32 +1085,32 @@ static int generate_sas_token_for_dps(
   current_unix_time = get_current_unix_time();
   EXIT_IF_TRUE(current_unix_time == 0, 0, "Failed getting current unix time.");
 
-  *expiration_time = current_unix_time + duration_in_minutes * 60;
+  *expiration_time = current_unix_time + duration_in_minutes * NUMBER_OF_SECONDS_IN_A_MINUTE;
 
   // Step 2.a.
-  plain_sas_signature = az_span_split(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(plain_sas_signature), 0, "Failed allocating buffer for plain sas token.");
+  plain_sas_signature = split_az_span(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(plain_sas_signature), 0, "Failed reserving buffer for plain sas token.");
 
   rc = az_iot_provisioning_client_sas_get_signature(
       provisioning_client, *expiration_time, plain_sas_signature, &plain_sas_signature);
-  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key");
+  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key.");
 
   // Step 2.b.
-  sas_signature = az_span_split(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_signature), 0, "Failed allocating buffer for sas_signature.");
+  sas_signature = split_az_span(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_signature), 0, "Failed reserving buffer for sas_signature.");
   
-  decoded_sas_key = az_span_split(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(decoded_sas_key), 0, "Failed allocating buffer for decoded_sas_key.");
+  decoded_sas_key = split_az_span(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(decoded_sas_key), 0, "Failed reserving buffer for decoded_sas_key.");
 
   result = data_manipulation_functions.base64_decode(
     az_span_ptr(device_key), az_span_size(device_key), az_span_ptr(decoded_sas_key), az_span_size(decoded_sas_key), &decoded_sas_key_length);
   EXIT_IF_TRUE(result != 0, 0, "Failed decoding SAS key.");
 
   // Step 2.c.
-  sas_hmac256_signed_signature = az_span_split(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_hmac256_signed_signature), 0, "Failed allocating buffer for sas_hmac256_signed_signature.");
+  sas_hmac256_signed_signature = split_az_span(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_hmac256_signed_signature), 0, "Failed reserving buffer for sas_hmac256_signed_signature.");
 
-  result = data_manipulation_functions.hmac_sha512_encrypt(
+  result = data_manipulation_functions.hmac_sha256_encrypt(
     az_span_ptr(decoded_sas_key), decoded_sas_key_length, 
     az_span_ptr(plain_sas_signature), az_span_size(plain_sas_signature), 
     az_span_ptr(sas_hmac256_signed_signature), az_span_size(sas_hmac256_signed_signature));
@@ -1155,32 +1176,32 @@ static int generate_sas_token_for_iot_hub(
   current_unix_time = get_current_unix_time();
   EXIT_IF_TRUE(current_unix_time == 0, 0, "Failed getting current unix time.");
 
-  *expiration_time = current_unix_time + duration_in_minutes * 60;
+  *expiration_time = current_unix_time + duration_in_minutes * NUMBER_OF_SECONDS_IN_A_MINUTE;
 
   // Step 2.a.
-  plain_sas_signature = az_span_split(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(plain_sas_signature), 0, "Failed allocating buffer for plain sas token.");
+  plain_sas_signature = split_az_span(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(plain_sas_signature), 0, "Failed reserving buffer for plain sas token.");
 
   rc = az_iot_hub_client_sas_get_signature(
       iot_hub_client, *expiration_time, plain_sas_signature, &plain_sas_signature);
-  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key");
+  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key.");
 
   // Step 2.b.
-  sas_signature = az_span_split(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_signature), 0, "Failed allocating buffer for sas_signature.");
+  sas_signature = split_az_span(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_signature), 0, "Failed reserving buffer for sas_signature.");
   
-  decoded_sas_key = az_span_split(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(decoded_sas_key), 0, "Failed allocating buffer for decoded_sas_key.");
+  decoded_sas_key = split_az_span(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(decoded_sas_key), 0, "Failed reserving buffer for decoded_sas_key.");
 
   result = data_manipulation_functions.base64_decode(
     az_span_ptr(device_key), az_span_size(device_key), az_span_ptr(decoded_sas_key), az_span_size(decoded_sas_key), &decoded_sas_key_length);
   EXIT_IF_TRUE(result != 0, 0, "Failed decoding SAS key.");
 
   // Step 2.c.
-  sas_hmac256_signed_signature = az_span_split(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_hmac256_signed_signature), 0, "Failed allocating buffer for sas_hmac256_signed_signature.");
+  sas_hmac256_signed_signature = split_az_span(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_hmac256_signed_signature), 0, "Failed reserving buffer for sas_hmac256_signed_signature.");
 
-  result = data_manipulation_functions.hmac_sha512_encrypt(
+  result = data_manipulation_functions.hmac_sha256_encrypt(
     az_span_ptr(decoded_sas_key), decoded_sas_key_length, 
     az_span_ptr(plain_sas_signature), az_span_size(plain_sas_signature), 
     az_span_ptr(sas_hmac256_signed_signature), az_span_size(sas_hmac256_signed_signature));
@@ -1207,32 +1228,45 @@ static int generate_sas_token_for_iot_hub(
   return mqtt_password_length;
 }
 
+/**
+ * @brief        Generates a custom payload for DPS registration request containing the Azure PnP model ID.
+ * @remark       This payload with the model ID is required for Azure IoT Central to properly
+ *               assign the IoT Plug and Play template.
+ * 
+ * @param[in]    mode_id        The string with the IoT Plug and Play model ID.
+ * @param[in]    data_buffer    Buffer where to write the resulting payload.
+ * @param[in]    remainder      The remainder space of `data_buffer` after enough is reserved for
+ *                              the resulting payload. 
+ * 
+ * @return       az_span        An az_span (reserved from `data_buffer`) containing the payload
+ *                              for the DPS registration request.
+ */
 static az_span generate_dps_register_custom_property(az_span model_id, az_span data_buffer, az_span* remainder)
 {
   az_span custom_property;
   size_t length = lengthof(DPS_REGISTER_CUSTOM_PAYLOAD_BEGIN) + az_span_size(model_id) + lengthof(DPS_REGISTER_CUSTOM_PAYLOAD_END);
       
-  custom_property = az_span_split(data_buffer, length, remainder);
-  EXIT_IF_TRUE(az_span_is_empty(custom_property), AZ_SPAN_EMPTY, "Failed generating DPS register custom property.");
+  custom_property = split_az_span(data_buffer, length, remainder);
+  EXIT_IF_TRUE(is_az_span_empty(custom_property), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (not enough space).");
 
   data_buffer = az_span_copy(data_buffer, AZ_SPAN_FROM_STR(DPS_REGISTER_CUSTOM_PAYLOAD_BEGIN));
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (prefix).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (prefix).");
   
   data_buffer = az_span_copy(data_buffer, model_id);
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (model id).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (model id).");
   
   data_buffer = az_span_copy(data_buffer, AZ_SPAN_FROM_STR(DPS_REGISTER_CUSTOM_PAYLOAD_END));
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (suffix).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (suffix).");
   
   return custom_property;
 }
 
 /* --- az_core extensions --- */
-az_span az_span_split(az_span span, int32_t size, az_span* remainder)
+az_span split_az_span(az_span span, int32_t size, az_span* remainder)
 {
   az_span result = az_span_slice(span, 0, size);
 
-  if (remainder != NULL && !az_span_is_empty(result))
+  if (remainder != NULL && !is_az_span_empty(result))
   {
     *remainder = az_span_slice(span, size, az_span_size(span));
   }
@@ -1240,16 +1274,16 @@ az_span az_span_split(az_span span, int32_t size, az_span* remainder)
   return result;
 }
 
-az_span az_span_slice_and_copy(az_span destination, az_span source, az_span* remainder)
+az_span slice_and_copy_az_span(az_span destination, az_span source, az_span* remainder)
 {
-  az_span result = az_span_split(destination, az_span_size(source), remainder);
+  az_span result = split_az_span(destination, az_span_size(source), remainder);
 
-  if (az_span_is_empty(*remainder))
+  if (is_az_span_empty(*remainder))
   {
     result = AZ_SPAN_EMPTY;
   }
 
-  if (!az_span_is_empty(result))
+  if (!is_az_span_empty(result))
   {
     (void)az_span_copy(result, source);
   }
diff --git a/examples/Azure_IoT_Central_ESP32/AzureIoT.h b/examples/Azure_IoT_Central_ESP32/AzureIoT.h
index a7a48e4..4cf5221 100644
--- a/examples/Azure_IoT_Central_ESP32/AzureIoT.h
+++ b/examples/Azure_IoT_Central_ESP32/AzureIoT.h
@@ -2,8 +2,10 @@
 // SPDX-License-Identifier: MIT
 
 /*
- * AzureIoT.cpp contains a state machine that implements those steps, plus abstractions to simplify
- * its overall use. Besides the basic configuration needed to access the Azure IoT services,
+ * AzureIoT.cpp contains a state machine that implements the necessary calls to azure-sdk-for-c
+ * for aiding to connect and work with Azure IoT services, plus abstractions to
+ * simplify overall use of azure-sdk-for-c.
+ * Besides the basic configuration needed to access the Azure IoT services,
  * all that is needed is to provide the functions required by that layer to:
  * - Interact with your MQTT client,
  * - Perform data manipulations (HMAC SHA256 encryption, Base64 decoding and encoding),
@@ -57,13 +59,13 @@ extern log_function_t default_logging_function;
 #endif // DISABLE_LOGGING
 
 
-/* --- Azure Abstraction --- */
+/* --- Azure Definitions --- */
 #define DPS_GLOBAL_ENDPOINT_FQDN          "global.azure-devices-provisioning.net"
-#define DPS_GLOBAL_ENDPOINT_PORT          8883
-#define IOT_HUB_ENDPOINT_PORT             8883
+#define DPS_GLOBAL_ENDPOINT_PORT          AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
+#define IOT_HUB_ENDPOINT_PORT             AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
 
 #define DEFAULT_SAS_TOKEN_LIFETIME_IN_MINUTES 60
-#define SAS_TOKEN_REFRESH_THRESHOLD_SECS 30 
+#define SAS_TOKEN_REFRESH_THRESHOLD_IN_SECS 30 
 
 /*
  * The structures below define a generic interface to abstract the interaction of this module, 
@@ -83,12 +85,13 @@ typedef enum mqtt_qos_t_enum
 mqtt_qos_t;
 
 /*
- * @brief     Defines a generic MQTT message to be exchanged between the AzureIoT.h layer
+ * @brief     Defines a generic MQTT message to be exchanged between the AzureIoT layer
  *            and the user application. 
  * @remark    It uses azure-sdk-for-c's az_span construct, which is merely a structure that
  *            has a pointer to a buffer and its size. Messages without a payload will have
  *            the `payload` member set to AZ_SPAN_EMPTY.
- *            Please see the az_span.h in azure-sdk-for-c for more details.
+ *            Please see the az_span.h in azure-sdk-for-c for more details at
+ *            https://azuresdkdocs.blob.core.windows.net/$web/c/az_core/1.2.0/az__span_8h.html
  */
 typedef struct mqtt_message_t_struct
 {
@@ -105,12 +108,12 @@ mqtt_message_t;
 typedef struct mqtt_client_config_t_struct
 {
   /*
-   * @brief    FQDN address of the broker the MQTT client shall connect to.
+   * @brief    FQDN address of the broker that the MQTT client shall connect to.
    */
   az_span address;
 
   /*
-   * @brief    Port of the broker the MQTT client shall connect to.
+   * @brief    Port of the broker that the MQTT client shall connect to.
    */
   int port;
 
@@ -133,12 +136,12 @@ mqtt_client_config_t;
 
 /*
  * @brief    Generic pointer to the actual instance of the application MQTT client.
- * @remark   set by the user application when the `mqtt_client_init_function_t` calback is invoked.
+ * @remark   set by the user application when the `mqtt_client_init_function_t` callback is invoked.
  */
 typedef void* mqtt_client_handle_t;
 
 /*
- * @brief         Function to initialize and connect a MQTT client.
+ * @brief         Function to initialize and connect an MQTT client.
  * @remark        When this function is called, it provides the information necessary to initialize a 
  *                specific MQTT client (whichever is used by the user application). In this callback
  *                it is expected that the MQTT client will be created/initialized, started and that it
@@ -155,7 +158,7 @@ typedef void* mqtt_client_handle_t;
 typedef int (*mqtt_client_init_function_t)(mqtt_client_config_t* mqtt_client_config, mqtt_client_handle_t* mqtt_client_handle);
 
 /*
- * @brief        Function to disconnect and deinitialize a MQTT client.
+ * @brief        Function to disconnect and deinitialize an MQTT client.
  * @remark       When this function is called the MQTT client instance referenced by `mqtt_client_handle` shall disconnect
  *               from the server and any functions of the MQTT client API that destroy the instance shall be called
  *               (so any allocated memory resources can be released).
@@ -193,10 +196,8 @@ typedef int (*mqtt_client_publish_function_t)(mqtt_client_handle_t mqtt_client_h
  *               `mqtt_client_handle`) to invoke the appropriate function in the MQTT client API to subscribe to 
  *               an MQTT topic.
  *
- * @param[in]    topic           The string containing the complete MQTT topic name to subscribed to.
+ * @param[in]    topic           The az_span with the string containing the complete MQTT topic name to subscribed to.
  *                               This string is always NULL-terminated.
- * @param[in]    topic_length    The length of `topic`. It can be used in case the MQTT client takes a 
- *                               topic name as a non-NULL-terminated string.
  * @param[in]    qos             MQTT QoS to be used for the topic subscription.
  * 
  *
@@ -204,7 +205,7 @@ typedef int (*mqtt_client_publish_function_t)(mqtt_client_handle_t mqtt_client_h
  *                               Azure IoT client expects `azure_iot_mqtt_client_subscribe_completed` to be called once the
  *                               MQTT client receives a SUBACK.
  */
-typedef int (*mqtt_client_subscribe_function_t)(mqtt_client_handle_t mqtt_client_handle, const uint8_t* topic, size_t topic_lenght, mqtt_qos_t qos);
+typedef int (*mqtt_client_subscribe_function_t)(mqtt_client_handle_t mqtt_client_handle, az_span topic, mqtt_qos_t qos);
 
 /*
  * @brief    Structure that consolidates all the abstracted MQTT functions.
@@ -213,13 +214,13 @@ typedef struct mqtt_client_interface_t_struct
 {
   mqtt_client_init_function_t mqtt_client_init;
   mqtt_client_deinit_function_t mqtt_client_deinit;
-  mqtt_client_subscribe_function_t mqtt_client_subscribe;
   mqtt_client_publish_function_t mqtt_client_publish;
+  mqtt_client_subscribe_function_t mqtt_client_subscribe;
 }
 mqtt_client_interface_t;
 
 /*
- * @brief    This function must be provided by the user for the AzureIoT.h layer
+ * @brief    This function must be provided by the user for the AzureIoT layer
  *           to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]     data              Buffer containing the Base64-encoded content.
@@ -234,14 +235,14 @@ mqtt_client_interface_t;
 typedef int (*base64_decode_function_t)(uint8_t* data, size_t data_length, uint8_t* decoded, size_t decoded_size, size_t* decoded_length);
 
 /*
- * @brief         This function must be provided by the user for the AzureIoT.h layer
+ * @brief         This function must be provided by the user for the AzureIoT layer
  *                to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]     data              Buffer containing the Base64-decoded content.
  * @param[in]     data_length       Length of `data`.
- * @param[in]     decoded           Buffer where to write the Base64-encoded content of `data`.
- * @param[in]     decoded_size      Size of `encoded`.
- * @param[out]    decoded_length    The final length of the Base64-encoded content written in 
+ * @param[in]     encoded           Buffer where to write the Base64-encoded content of `data`.
+ * @param[in]     encoded_size      Size of `encoded`.
+ * @param[out]    encoded_length    The final length of the Base64-encoded content written in 
  *                                  the `encoded` buffer.
  * 
  * @return        int               0 on success, or non-zero if any failure occurs.
@@ -249,19 +250,19 @@ typedef int (*base64_decode_function_t)(uint8_t* data, size_t data_length, uint8
 typedef int (*base64_encode_function_t)(uint8_t* data, size_t data_length, uint8_t* encoded, size_t encoded_size, size_t* encoded_length);
 
 /*
- * @brief        This function must be provided by the user for the AzureIoT.h layer
+ * @brief        This function must be provided by the user for the AzureIoT layer
  *               to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]    key                       Encryption key to be used in the HMAC-SHA256 algorithm.
  * @param[in]    key_length                Length of `key`.
  * @param[in]    payload                   Buffer containing the data to be encrypted.
  * @param[in]    payload_size              Size of `payload`.
- * @param[in]    encrypted_payload         Buffer where to write teh HMAC-SHA256 encrypted content of `payload`.
+ * @param[in]    encrypted_payload         Buffer where to write the HMAC-SHA256 encrypted content of `payload`.
  * @param[in]    encrypted_payload_size    The size of the `encrypted_payload` buffer.
  * 
  * @return       int                       0 on success, or non-zero if any failure occurs.
  */
-typedef int (*hmac_sha512_encryption_function_t)(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* encrypted_payload, size_t encrypted_payload_size);
+typedef int (*hmac_sha256_encryption_function_t)(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* encrypted_payload, size_t encrypted_payload_size);
 
 /*
  * @brief    Structure that consolidates all the data manipulation functions.
@@ -270,7 +271,7 @@ typedef struct data_manipulation_functions_t_struct
 {
   base64_decode_function_t base64_decode;
   base64_encode_function_t base64_encode;
-  hmac_sha512_encryption_function_t hmac_sha512_encrypt;
+  hmac_sha256_encryption_function_t hmac_sha256_encrypt;
 }
 data_manipulation_functions_t;
 
@@ -295,7 +296,7 @@ typedef void (*properties_update_completed_t)(uint32_t request_id, az_iot_status
 typedef void (*properties_received_t)(az_span properties);
 
 /*
- * @brief    Structure containing all the details of a Azure Plug and Play Command.
+ * @brief    Structure containing all the details of a IoT Plug and Play Command.
  */
 typedef struct command_request_t_struct
 {
@@ -323,7 +324,7 @@ typedef struct command_request_t_struct
 command_request_t;
 
 /*
- * @brief        Defines the callback for receiving an Azure Plug-and-Play Command.
+ * @brief        Defines the callback for receiving an IoT Plug and Play Command.
  * @remark       A response for this command MUST be provided to Azure by calling 
  *               `azure_iot_send_command_response`.
  * 
@@ -335,7 +336,7 @@ command_request_t;
 typedef void (*command_request_received_t)(command_request_t command);
 
 /*
- * @brief    All the possible status returned by `azure_iot_get_status`.
+ * @brief    All the possible statuses returned by `azure_iot_get_status`.
  */
 typedef enum azure_iot_status_t_struct
 {
@@ -407,7 +408,7 @@ azure_iot_client_state_t;
  *           Also make sure that the instance of `azure_iot_config_t` (and its members) do not
  *           lose scope throughout the lifetime of the Azure IoT client.
  *           Most of the members of this structure use az_span for encapsulating a buffer and
- *           its size. For more details on az_span, please explorer the code at 
+ *           its size. For more details on az_span, please explore the code at 
  *           https://github.com/azure/azure-sdk-for-c.
  */
 typedef struct azure_iot_config_t_struct
@@ -447,8 +448,8 @@ typedef struct azure_iot_config_t_struct
   az_span device_id;
 
   /*
-   * @brief     Symetric key of the device to authenticate as when connecting to Azure IoT Hub.
-   * @remark    This key will be used to generate the MQTT client password, is using SAS-token
+   * @brief     Symmetric key of the device to authenticate as when connecting to Azure IoT Hub.
+   * @remark    This key will be used to generate the MQTT client password, if using SAS-token
    *            authentication (which is used, for example, when connecting to Azure IoT Central).
    */
   az_span device_key;
@@ -456,7 +457,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     The "Registration ID" to authenticate with when connecting to
    *            Azure Device Provisioning service.
-   * @remark    This information only when performing device-provisioning (which is used,
+   * @remark    This information is only needed when performing device-provisioning (which is used,
                 for example, when connecting to Azure IoT Central). If device-provisioning is
                 not being used (i.e., Azure IoT client is connecting directly to Azure IoT Hub)
                 this member MUST be set with AZ_SPAN_EMPTY.
@@ -468,7 +469,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     The "ID Scope" to authenticate with when connecting to
    *            Azure Device Provisioning service.
-   * @remark    This information only when performing device-provisioning (which is used,
+   * @remark    This information is only needed when performing device-provisioning (which is used,
                 for example, when connecting to Azure IoT Central). If device-provisioning is
                 not being used (i.e., Azure IoT client is connecting directly to Azure IoT Hub)
                 this member MUST be set with AZ_SPAN_EMPTY.
@@ -476,8 +477,8 @@ typedef struct azure_iot_config_t_struct
   az_span dps_id_scope;
 
   /*
-   * @brief     Model ID of the Azure Plug-and-Play template implemented by the user application.
-   * @remark    This is used only when the application uses/implements Azure IoT Plug-and-Play.
+   * @brief     Model ID of the IoT Plug and Play template implemented by the user application.
+   * @remark    This is used only when the application uses/implements IoT Plug and Play.
    */
   az_span model_id;
 
@@ -533,9 +534,9 @@ typedef struct azure_iot_config_t_struct
 
   /*
    * @brief    Amount of minutes for which the MQTT password should be valid.
-   * @remark   If set to zero, Azure Iot client sets it to the default value of 60 minutes.
+   * @remark   If set to zero, Azure IoT client sets it to the default value of 60 minutes.
    *           Once this amount of minutes has passed and the MQTT password is expired,
-   *           Azure IoT client trigers its logic to generate a new password and reconnect with
+   *           Azure IoT client triggers its logic to generate a new password and reconnect with
    *           Azure IoT Hub.
    */
   uint32_t sas_token_lifetime_in_minutes;
@@ -543,7 +544,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     Callback handler used by Azure IoT client to inform the user application of
    *            a completion of properties update.
-   * @remark    A properties update is trigered by the user application when
+   * @remark    A properties update is triggered by the user application when
    *            `azure_iot_send_properties_update` is called.
    */
   properties_update_completed_t on_properties_update_completed;
@@ -551,7 +552,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     Callback handler used by Azure IoT client to inform the user application of
    *            a writable-properties update received from Azure IoT Hub.
-   * @remark    If Azure IoT Plug.-and-Play is used, a response must be sent back to
+   * @remark    If IoT Plug and Play is used, a response must be sent back to
    *            Azure IoT Hub.
    */
   properties_received_t on_properties_received;
@@ -590,7 +591,7 @@ typedef struct azure_iot_t_struct
 azure_iot_t;
 
 /*
- * @brief        Initialies the azure_iot_t structure that holds the Azure IoT client state.
+ * @brief        Initializes the azure_iot_t structure that holds the Azure IoT client state.
  * @remark       This function must be called only once per `azure_iot_t` instance,
  *               before any other function can be called using it.
  * 
@@ -598,9 +599,9 @@ azure_iot_t;
  * @param[in]    azure_iot_config    A pointer to a `azure_iot_config_t` containing all the
  *                                   configuration neeeded for the client to connect and work with
  *                                   the Azure IoT services.
- * @return       int                 0 on success, or non-zero if any failure occurs.
+ * @return                           Nothing.
  */
-int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config);
+void azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config);
 
 /*
  * @brief        Starts an Azure IoT client.
@@ -673,23 +674,23 @@ void azure_iot_do_work(azure_iot_t* azure_iot);
 int azure_iot_send_telemetry(azure_iot_t* azure_iot, az_span message);
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief        Sends a property update message to Azure IoT Hub.
  *
- * @param[in]    azure_iot                         The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
- * @param[in]    message                           An `az_span` with the message with the reported properties update
- *                                                 (a JSON document formatted according to the DTDL specification).
- *                                                 `message` gets passed as-is to the MQTT client publish function as the payload, so if 
- *                                                 your MQTT client expects a null-terminated string for payload, make sure `message` is
- *                                                 a null-terminated string.
- * @param[in]    request_id                        An unique identification number to correlate the response with when
- *                                                 `on_properties_update_completed` (set in azure_iot_config_t) is invoked.
+ * @param[in]    azure_iot     The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
+ * @param[in]    request_id    An unique identification number to correlate the response with when
+ * @param[in]    message       An `az_span` with the message with the reported properties update
+ *                             (a JSON document formatted according to the DTDL specification).
+ *                             `message` gets passed as-is to the MQTT client publish function as the payload, so if 
+ *                             your MQTT client expects a null-terminated string for payload, make sure `message` is
+ *                             a null-terminated string.
+ *                             `on_properties_update_completed` (set in azure_iot_config_t) is invoked.
  *
- * @return       int                               0 if the function succeeds, or non-zero if any failure occurs.
+ * @return       int           0 if the function succeeds, or non-zero if any failure occurs.
  */
 int azure_iot_send_properties_update(azure_iot_t* azure_iot, uint32_t request_id, az_span message);
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief        Sends a property update message to Azure IoT Hub.
  *
  * @param[in]    azure_iot          The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
  * @param[in]    request_id         The same `request_id` of the device command received from Azure IoT Hub.
@@ -720,7 +721,7 @@ int azure_iot_mqtt_client_connected(azure_iot_t* azure_iot);
 /*
  * @brief        Informs the Azure IoT client that the MQTT client is disconnected.
  * @remark       This must be called after Azure IoT client invokes the `mqtt_client_deinit` callback
- *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has disconencted
+ *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has disconnected
  *               from the Azure IoT service.
  * 
  * @param[in]    azure_iot    A pointer to the instance of `azure_iot_t` previously initialized by the caller.
@@ -746,7 +747,7 @@ int azure_iot_mqtt_client_subscribe_completed(azure_iot_t* azure_iot, int packet
  * @brief        Informs the Azure IoT client that the MQTT client has completed a PUBLISH.
  * @remark       This must be called after Azure IoT client invokes the `mqtt_client_publish` callback
  *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has
- *               completed a MQTT PUBLISH. If the QoS is 0 (AT MOST ONCE), this shall be called by 
+ *               completed an MQTT PUBLISH. If the QoS is 0 (AT MOST ONCE), this shall be called by 
  *               the user application right after `mqtt_client_publish` is invoked. If the QoS of
  *               is 1 (AT LEAST ONCE), this shall be called whenever a PUBACK is received.
  * 
@@ -776,13 +777,13 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
  */
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief Checks whether `span` is equal to AZ_SPAN_EMPTY.
  *
  * @param[in]    span           A span to be verified.
  *
  * @return       boolean        True if `span`'s pointer and size are equal to AZ_SPAN_EMPTY, or false otherwise.
  */
-#define az_span_is_empty(span) az_span_is_content_equal(span, AZ_SPAN_EMPTY)
+#define is_az_span_empty(span) az_span_is_content_equal(span, AZ_SPAN_EMPTY)
 
 /**
  * @brief Slices `span` at position `size`, returns the first slice and assigns the second slice to `remainder`.
@@ -793,7 +794,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
  *
  * @return       az_span        A slice of `span` from position zero to `size`.
  */
-az_span az_span_split(az_span span, int32_t size, az_span* remainder);
+az_span split_az_span(az_span span, int32_t size, az_span* remainder);
 
 /**
  * @brief Slices `destination` to fit `source`, copy `source` into the first slice and returns the second through `remainder`.
@@ -804,6 +805,6 @@ az_span az_span_split(az_span span, int32_t size, az_span* remainder);
  *
  * @return       az_span        A slice of `destination` with the same size as `source`, with `source`'s content copied over.
  */
-static az_span az_span_slice_and_copy(az_span destination, az_span source, az_span* remainder);
+static az_span slice_and_copy_az_span(az_span destination, az_span source, az_span* remainder);
 
 #endif // AZURE_IOT_H
diff --git a/examples/Azure_IoT_Central_ESP32/Azure_IoT_Central_ESP32.ino b/examples/Azure_IoT_Central_ESP32/Azure_IoT_Central_ESP32.ino
index e5b383a..c6e264f 100644
--- a/examples/Azure_IoT_Central_ESP32/Azure_IoT_Central_ESP32.ino
+++ b/examples/Azure_IoT_Central_ESP32/Azure_IoT_Central_ESP32.ino
@@ -6,9 +6,9 @@
  * It uses our Azure Embedded SDK for C to help interact with Azure IoT.
  * For reference, please visit https://github.com/azure/azure-sdk-for-c and https://azureiotcentral.com/.
  * 
- * To connect and work with Azure IoT Hub you need a MQTT client, connecting, subscribing
+ * To connect and work with Azure IoT Hub you need an MQTT client, connecting, subscribing
  * and publishing to specific topics to use the messaging features of the hub.
- * Our azure-sdk-for-c is a MQTT client support library, helping composing and parsing the
+ * Our azure-sdk-for-c is an MQTT client support library, helping composing and parsing the
  * MQTT topic names and messages exchanged with the Azure IoT Hub.
  * 
  * The additional layers in this sketch provide a structured use of azure-sdk-for-c and
@@ -22,8 +22,8 @@
  * - Perform data manipulations (HMAC SHA256 encryption, Base64 decoding and encoding),
  * - Receive the callbacks for Plug and Play properties and commands.
  * 
- * Azure_IoT_PnP_Template.cpp contains the actual implementation of the Azure Plug-and-Play template
- * specific for the Espressif ESP32 Azure IoT Kit board.
+ * Azure_IoT_PnP_Template.cpp contains the actual implementation of the IoT Plug and Play template
+ * specific for the Espressif ESP32 board.
  * 
  * To properly connect to your Azure IoT services, please fill the information in the `iot_configs.h` file. 
  */
@@ -197,13 +197,13 @@ static int mqtt_client_deinit_function(mqtt_client_handle_t mqtt_client_handle)
 /*
  * See the documentation of `mqtt_client_subscribe_function_t` in AzureIoT.h for details.
  */
-static int mqtt_client_subscribe_function(mqtt_client_handle_t mqtt_client_handle, const uint8_t* topic, size_t topic_length, mqtt_qos_t qos)
+static int mqtt_client_subscribe_function(mqtt_client_handle_t mqtt_client_handle, az_span topic, mqtt_qos_t qos)
 {
-  LogInfo("MQTT client subscribing to '%s'", topic);
+  LogInfo("MQTT client subscribing to '%.*s'", az_span_size(topic), az_span_ptr(topic));
        
   // As per documentation, `topic` always ends with a null-terminator.
   // esp_mqtt_client_subscribe returns the packet id or negative on error already, so no conversion is needed.
-  int packet_id = esp_mqtt_client_subscribe((esp_mqtt_client_handle_t)mqtt_client_handle, (const char*)topic, (int)qos);
+  int packet_id = esp_mqtt_client_subscribe((esp_mqtt_client_handle_t)mqtt_client_handle, (const char*)az_span_ptr(topic), (int)qos);
 
   return packet_id;
 }
@@ -236,7 +236,7 @@ static int mqtt_client_publish_function(mqtt_client_handle_t mqtt_client_handle,
 /* --- Other Interface functions required by Azure IoT --- */
 
 /*
- * See the documentation of `hmac_sha512_encryption_function_t` in AzureIoT.h for details.
+ * See the documentation of `hmac_sha256_encryption_function_t` in AzureIoT.h for details.
  */
 static int mbedtls_hmac_sha256(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* signed_payload, size_t signed_payload_size)
 {
@@ -324,7 +324,7 @@ void setup()
 
   /* 
    * The configuration structure used by Azure IoT must remain unchanged (including data buffer) 
-   * throughout the lifetime of the sample. This variable must also not loose context so other
+   * throughout the lifetime of the sample. This variable must also not lose context so other
    * components do not overwrite any information within this structure.
    */
   azure_iot_config.user_agent = AZ_SPAN_FROM_STR(AZURE_SDK_CLIENT_USER_AGENT_WORKAROUND);
@@ -341,22 +341,17 @@ void setup()
   azure_iot_config.mqtt_client_interface.mqtt_client_deinit = mqtt_client_deinit_function;
   azure_iot_config.mqtt_client_interface.mqtt_client_subscribe = mqtt_client_subscribe_function;
   azure_iot_config.mqtt_client_interface.mqtt_client_publish = mqtt_client_publish_function;
-  azure_iot_config.data_manipulation_functions.hmac_sha512_encrypt = mbedtls_hmac_sha256;
+  azure_iot_config.data_manipulation_functions.hmac_sha256_encrypt = mbedtls_hmac_sha256;
   azure_iot_config.data_manipulation_functions.base64_decode = base64_decode;
   azure_iot_config.data_manipulation_functions.base64_encode = base64_encode;
   azure_iot_config.on_properties_update_completed = on_properties_update_completed;
   azure_iot_config.on_properties_received = on_properties_received;
   azure_iot_config.on_command_request_received = on_command_request_received;
 
-  if (azure_iot_init(&azure_iot, &azure_iot_config) != 0)
-  {
-    LogError("Failed initializing the Azure IoT client.");
-  }
-  else
-  {
-    LogInfo("Azure IoT client initialized (state=%d)", azure_iot.state);
-    azure_iot_start(&azure_iot);
-  }
+  azure_iot_init(&azure_iot, &azure_iot_config);
+  azure_iot_start(&azure_iot);
+
+  LogInfo("Azure IoT client initialized (state=%d)", azure_iot.state);
 }
 
 void loop()
@@ -445,7 +440,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
     int i, r;
 
     case MQTT_EVENT_ERROR:
-     LogError("MQTT client in ERROR state.");
+      LogError("MQTT client in ERROR state.");
       LogError( 
         "esp_tls_stack_err=%d; esp_tls_cert_verify_flags=%d;esp_transport_sock_errno=%d;error_type=%d;connect_return_code=%d",  
         event->error_handle->esp_tls_stack_err,
@@ -475,7 +470,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
           LogError("connect_return_code=MQTT_CONNECTION_REFUSE_NOT_AUTHORIZED"); 
           break; 
         default: 
-          LogError("connect_return_code=unknown"); 
+          LogError("connect_return_code=unknown (%d)", event->error_handle->connect_return_code); 
           break; 
       };
 
@@ -537,7 +532,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
       LogInfo("MQTT client connecting.");
       break;
     default:
-      LogError("MQTT event UNKNOWN");
+      LogError("MQTT event UNKNOWN.");
       break;
   }
 
diff --git a/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.cpp b/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.cpp
index ce3123b..b98ce42 100644
--- a/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.cpp
+++ b/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.cpp
@@ -351,7 +351,7 @@ static int generate_telemetry_payload(uint8_t* payload_buffer, size_t payload_bu
 
   if ((payload_buffer_size - az_span_size(payload_buffer_span)) < 1)
   {
-    LogError("Insuficient space for telemetry payload null terminator.");
+    LogError("Insufficient space for telemetry payload null terminator.");
     return RESULT_ERROR;
   }
 
@@ -428,7 +428,7 @@ static int generate_device_info_payload(az_iot_hub_client const* hub_client, uin
 
   if ((payload_buffer_size - az_span_size(payload_buffer_span)) < 1)
   {
-    LogError("Insuficient space for telemetry payload null terminator.");
+    LogError("Insufficient space for telemetry payload null terminator.");
     return RESULT_ERROR;
   }
 
@@ -526,7 +526,7 @@ static int consume_properties_and_generate_response(
     }
     else
     {
-      LogError("Unexpected property received (%.*s)",
+      LogError("Unexpected property received (%.*s).",
         az_span_size(jr.token.slice), az_span_ptr(jr.token.slice));
     }
 
diff --git a/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.h b/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.h
index b9db855..c8e5284 100644
--- a/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.h
+++ b/examples/Azure_IoT_Central_ESP32/Azure_IoT_PnP_Template.h
@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: MIT
 
 /*
- * Azure_IoT_PnP_Template.cpp implements the the Azure Plug-and-Play template
+ * Azure_IoT_PnP_Template.cpp implements the IoT Plug and Play template
  * specific for the Espressif ESP32 Azure IoT Kit board.
  */
  
@@ -19,8 +19,8 @@
 void azure_pnp_init();
 
 /*
- * @brief     Returns the model id of the Azure Plug and Play template implemented by this module.
- * @remark    Every Azure Plug and Play template has a model id that must be informed by the 
+ * @brief     Returns the model id of the IoT Plug and Play template implemented by this device.
+ * @remark    Every IoT Plug and Play template has a model id that must be informed by the 
  *            device during Azure IoT provisioning and connection with the Azure IoT Hub.
  * @return    az_span       An `az_span` containing the model id implemented by this module.
  */
@@ -52,12 +52,12 @@ int azure_pnp_send_device_info(azure_iot_t* azure_iot, uint32_t request_id);
 void azure_pnp_set_telemetry_frequency(size_t frequency_in_seconds);
 
 /*
- * @brief     Sends telemetry implemented by this Azure Plug and Play application to Azure IoT Central.
- * @remark    The Azure Plug and Play template implemented by this module is specific to the
+ * @brief     Sends telemetry implemented by this IoT Plug and Play application to Azure IoT Central.
+ * @remark    The IoT Plug and Play template implemented by this device is specific to the
  *            Espressif ESP32 Azure IoT Kit board, which contains several sensors.
  *            The template defines telemetry data points for temperature, humidity, 
  *            pressure, altitude, luminosity, magnetic field, rolling and pitch angles, 
- *            as well as acceleration. All of these data is read from the board sensors and sent to 
+ *            as well as acceleration. All of these data are read from the board sensors and sent to 
  *            Azure IoT Central when `azure_pnp_send_telemetry` is called.
  *            This function must be called frequently enough, no slower than the frequency set
  *            with `azure_pnp_set_telemetry_frequency` (or the default frequency of 10 seconds).
@@ -72,7 +72,7 @@ int azure_pnp_send_telemetry(azure_iot_t* azure_iot);
 /*
  * @brief     Handles a command when it is received from Azure IoT Central.
  * @remark    This function will perform the task requested by the command received 
- *            (if the command matches the expected name) and send back a response to 
+ *            (if the command matches the expected name) and sends back a response to 
  *            Azure IoT Central.
  *
  * @param[in]    azure_iot          A pointer to a azure_iot_t instance, previously initialized 
diff --git a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.cpp b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.cpp
index 6b5b5a0..cc5ab2a 100644
--- a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.cpp
+++ b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.cpp
@@ -15,8 +15,8 @@
 log_function_t default_logging_function = NULL;
 #endif // DISABLE_LOGGING
 
-/* --- Azure Abstractions --- */
-#define IOT_HUB_MQTT_PORT                           8883
+/* --- Azure Definitions --- */
+#define IOT_HUB_MQTT_PORT                           AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
 #define MQTT_PROTOCOL_PREFIX                        "mqtts://"
 #define DPS_GLOBAL_ENDPOINT_MQTT_URI                MQTT_PROTOCOL_PREFIX DPS_GLOBAL_ENDPOINT_FQDN
 #define DPS_GLOBAL_ENDPOINT_MQTT_URI_WITH_PORT      DPS_GLOBAL_ENDPOINT_MQTT_URI ":" STR(DPS_GLOBAL_ENDPOINT_PORT)
@@ -32,6 +32,8 @@ log_function_t default_logging_function = NULL;
 #define DPS_REGISTER_CUSTOM_PAYLOAD_BEGIN           "{\"modelId\":\""
 #define DPS_REGISTER_CUSTOM_PAYLOAD_END             "\"}"
 
+#define NUMBER_OF_SECONDS_IN_A_MINUTE               60
+
 #define EXIT_IF_TRUE(condition, retcode, message, ...)                              \
   do                                                                                \
   {                                                                                 \
@@ -71,17 +73,17 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
 static az_span generate_dps_register_custom_property(az_span model_id, az_span data_buffer, az_span* remainder);
 
 #define is_device_provisioned(azure_iot) \
-  (!az_span_is_empty(azure_iot->config->iot_hub_fqdn) && !az_span_is_empty(azure_iot->config->device_id))
+  (!is_az_span_empty(azure_iot->config->iot_hub_fqdn) && !is_az_span_empty(azure_iot->config->device_id))
 
 /* --- Public API --- */
-int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
+void azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
 {
   _az_PRECONDITION_NOT_NULL(azure_iot);
   _az_PRECONDITION_NOT_NULL(azure_iot_config);
   if (azure_iot_config->use_device_provisioning)
   {
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->iot_hub_fqdn));
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->device_id));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->iot_hub_fqdn));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->device_id));
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->dps_id_scope, 1, false);
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->dps_registration_id, 1, false);
   }
@@ -89,14 +91,14 @@ int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
   {
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->iot_hub_fqdn, 1, false);
     _az_PRECONDITION_VALID_SPAN(azure_iot_config->device_id, 1, false);
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->dps_id_scope));
-    _az_PRECONDITION(az_span_is_empty(azure_iot_config->dps_registration_id));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->dps_id_scope));
+    _az_PRECONDITION(is_az_span_empty(azure_iot_config->dps_registration_id));
   }
   _az_PRECONDITION_VALID_SPAN(azure_iot_config->device_key, 1, false);
   _az_PRECONDITION_VALID_SPAN(azure_iot_config->data_buffer, 1, false);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.base64_decode);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.base64_encode);
-  _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.hmac_sha512_encrypt);
+  _az_PRECONDITION_NOT_NULL(azure_iot_config->data_manipulation_functions.hmac_sha256_encrypt);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_init);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_deinit);
   _az_PRECONDITION_NOT_NULL(azure_iot_config->mqtt_client_interface.mqtt_client_subscribe);
@@ -115,8 +117,6 @@ int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config)
   {
     azure_iot->config->sas_token_lifetime_in_minutes = DEFAULT_SAS_TOKEN_LIFETIME_IN_MINUTES;
   }
-
-  return RESULT_OK;
 }
 
 int azure_iot_start(azure_iot_t* azure_iot)
@@ -237,7 +237,8 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
   size_t length;
   mqtt_client_config_t mqtt_client_config;
   mqtt_message_t mqtt_message;
-  az_span data_buffer, dps_register_custom_property;
+  az_span data_buffer;
+  az_span dps_register_custom_property;
       
   switch (azure_iot->state)
   {
@@ -250,7 +251,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         // This seems harmless, but...
         // azure_iot->config->data_buffer always points to the original buffer provided by the user.
-        // azure_iot->data_buffer is an intermediate pointer. It starts by pointint to azure_iot->config->data_buffer.
+        // azure_iot->data_buffer is an intermediate pointer. It starts by pointing to azure_iot->config->data_buffer.
         // In the steps below the code might need to retain part of azure_iot->data_buffer for saving some critical information,
         // namely the DPS operation id, the provisioned IoT Hub FQDN and provisioned Device ID (if provisioning is being used).
         // In these cases, azure_iot->data_buffer will then point to `the remaining available space` of azure_iot->config->data_buffer
@@ -277,6 +278,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed initializing MQTT client.");
+        return;
       }
 
       break;
@@ -288,14 +290,14 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
 
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
           azure_iot->mqtt_client_handle, 
-          (const uint8_t*)AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC),
+          AZ_SPAN_FROM_STR(AZ_IOT_PROVISIONING_CLIENT_REGISTER_SUBSCRIBE_TOPIC),
           mqtt_qos_at_most_once);
           
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed subscribing to Azure Device Provisioning respose topic.");
+        return;
       }
 
       break;
@@ -314,19 +316,19 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
         return;
       }
 
-      mqtt_message.topic = az_span_split(data_buffer, length, &data_buffer);
+      mqtt_message.topic = split_az_span(data_buffer, length, &data_buffer);
 
-      if (az_span_is_empty(mqtt_message.topic) || az_span_is_empty(data_buffer))
+      if (is_az_span_empty(mqtt_message.topic) || is_az_span_empty(data_buffer))
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed allocating memory for DPS register payload.");
+        LogError("Failed reserving memory for DPS register payload.");
         return;
       }
 
       dps_register_custom_property = generate_dps_register_custom_property(
         azure_iot->config->model_id, data_buffer, &mqtt_message.payload);
 
-      if (az_span_is_empty(dps_register_custom_property))
+      if (is_az_span_empty(dps_register_custom_property))
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed generating DPS register custom property payload.");
@@ -359,6 +361,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed publishing to DPS registration topic");
+        return;
       }
 
       break;
@@ -405,6 +408,7 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       {
         azure_iot->state = azure_iot_state_error;
         LogError("Failed publishing to DPS status query topic");
+        return;
       }
 
       break;
@@ -437,7 +441,8 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       if (azure_iot->config->mqtt_client_interface.mqtt_client_init(&mqtt_client_config, &azure_iot->mqtt_client_handle) != 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed initializing MQTT client.");
+        LogError("Failed initializing MQTT client for IoT Hub connection.");
+        return;
       }
 
       break;
@@ -447,13 +452,15 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       azure_iot->state = azure_iot_state_subscribing_to_pnp_cmds;
       
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_COMMANDS_SUBSCRIBE_TOPIC),
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play commands topic.");
+        LogError("Failed subscribing to IoT Plug and Play commands topic.");
+        return;
       }
 
       break;
@@ -463,30 +470,33 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
       azure_iot->state = azure_iot_state_subscribing_to_pnp_props;
 
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC, 
-          lengthof(AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_PROPERTIES_MESSAGE_SUBSCRIBE_TOPIC), 
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play properties topic.");
+        LogError("Failed subscribing to IoT Plug and Play properties topic.");
+        return;
       }
-    
-      break;
 
+      break;
     case azure_iot_state_subscribing_to_pnp_props:
       break;
     case azure_iot_state_subscribed_to_pnp_props:
       azure_iot->state = azure_iot_state_subscribing_to_pnp_writable_props;
     
       packet_id = azure_iot->config->mqtt_client_interface.mqtt_client_subscribe(
-          azure_iot->mqtt_client_handle, (const uint8_t*)AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC,
-          lengthof(AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC), mqtt_qos_at_least_once);
+          azure_iot->mqtt_client_handle,
+          AZ_SPAN_FROM_STR(AZ_IOT_HUB_CLIENT_PROPERTIES_WRITABLE_UPDATES_SUBSCRIBE_TOPIC),
+          mqtt_qos_at_least_once);
 
       if (packet_id < 0)
       {
         azure_iot->state = azure_iot_state_error;
-        LogError("Failed subscribing to Azure Plug and Play writable properties topic.");
+        LogError("Failed subscribing to IoT Plug and Play writable properties topic.");
+        return;
       }
 
       break;
@@ -501,13 +511,14 @@ void azure_iot_do_work(azure_iot_t* azure_iot)
         azure_iot->state = azure_iot_state_error;
         LogError("Failed getting current time for checking SAS token expiration.");
       }
-      else if ((azure_iot->sas_token_expiration_time - now) < SAS_TOKEN_REFRESH_THRESHOLD_SECS)
+      else if ((azure_iot->sas_token_expiration_time - now) < SAS_TOKEN_REFRESH_THRESHOLD_IN_SECS)
       {
         azure_iot->state = azure_iot_state_refreshing_sas;
         if (azure_iot->config->mqtt_client_interface.mqtt_client_deinit(&azure_iot->mqtt_client_handle) != 0)
         {
           azure_iot->state = azure_iot_state_error;
           LogError("Failed de-initializing MQTT client.");
+          return;
         }
       }
       break;
@@ -559,7 +570,7 @@ int azure_iot_send_properties_update(azure_iot_t* azure_iot, uint32_t request_id
 
   azr = az_iot_hub_client_properties_get_reported_publish_topic(
       &azure_iot->iot_hub_client, request_id_span, (char*)az_span_ptr(data_buffer), az_span_size(data_buffer), &topic_length);
-  EXIT_IF_AZ_FAILED(azr, RESULT_ERROR, "Failed to get the repoted properties publish topic");
+  EXIT_IF_AZ_FAILED(azr, RESULT_ERROR, "Failed to get the reported properties publish topic");
 
   mqtt_message.topic = az_span_slice(data_buffer, 0, topic_length);
   mqtt_message.payload = message;
@@ -690,7 +701,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
   {
     // This message should either be:
     // - a response to a properties update request, or
-    // - a response to a get properties request, or
+    // - a response to a "get" properties request, or
     // - a command request.
 
     az_iot_hub_client_properties_message property_message;
@@ -725,7 +736,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
             
             if (az_result_failed(az_span_atou32(property_message.request_id, &request_id)))
             {
-              LogError("Failed parsing properties update request id (%.*s)", 
+              LogError("Failed parsing properties update request id (%.*s).", 
                 az_span_size(property_message.request_id), az_span_ptr(property_message.request_id));
               result = RESULT_ERROR;
             }
@@ -789,14 +800,14 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
       {
         result = RESULT_OK;
 
-        if (az_span_is_empty(azure_iot->dps_operation_id))
+        if (is_az_span_empty(azure_iot->dps_operation_id))
         {
-          azure_iot->dps_operation_id = az_span_slice_and_copy(azure_iot->data_buffer, register_response.operation_id, &azure_iot->data_buffer);
+          azure_iot->dps_operation_id = slice_and_copy_az_span(azure_iot->data_buffer, register_response.operation_id, &azure_iot->data_buffer);
 
-          if (az_span_is_empty(azure_iot->dps_operation_id))
+          if (is_az_span_empty(azure_iot->dps_operation_id))
           {
             azure_iot->state = azure_iot_state_error;
-            LogError("Failed allocating memory for DPS operation id.");
+            LogError("Failed reserving memory for DPS operation id.");
             result = RESULT_ERROR;
           }
         }
@@ -812,9 +823,9 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
         az_span data_buffer = azure_iot->config->data_buffer; // Operation ID is no longer needed.
         azure_iot->data_buffer = data_buffer; // In case any step below fails.
 
-        azure_iot->config->iot_hub_fqdn = az_span_slice_and_copy(data_buffer, register_response.registration_state.assigned_hub_hostname, &data_buffer);
+        azure_iot->config->iot_hub_fqdn = slice_and_copy_az_span(data_buffer, register_response.registration_state.assigned_hub_hostname, &data_buffer);
         
-        if (az_span_is_empty(azure_iot->config->iot_hub_fqdn))
+        if (is_az_span_empty(azure_iot->config->iot_hub_fqdn))
         {
           azure_iot->state = azure_iot_state_error;
           LogError("Failed saving IoT Hub fqdn from provisioning.");
@@ -822,9 +833,9 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
         }
         else
         {
-          azure_iot->config->device_id = az_span_slice_and_copy(data_buffer, register_response.registration_state.device_id, &data_buffer);
+          azure_iot->config->device_id = slice_and_copy_az_span(data_buffer, register_response.registration_state.device_id, &data_buffer);
                     
-          if (az_span_is_empty(azure_iot->config->device_id))
+          if (is_az_span_empty(azure_iot->config->device_id))
           {
             azure_iot->state = azure_iot_state_error;
             LogError("Failed saving device id from provisioning.");
@@ -848,7 +859,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
   }
   else
   {
-    LogError("No PUBLISH notification expected");
+    LogError("No PUBLISH notification expected.");
     result = RESULT_ERROR;
   }
   
@@ -870,7 +881,7 @@ int azure_iot_send_command_response(azure_iot_t* azure_iot, az_span request_id,
   azrc = az_iot_hub_client_commands_response_get_publish_topic(
       &azure_iot->iot_hub_client, request_id, response_status, 
       (char*)az_span_ptr(mqtt_message.topic), az_span_size(mqtt_message.topic), &topic_length);
-  EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed to get the commands response topic");
+  EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed to get the commands response topic.");
 
   mqtt_message.topic = az_span_slice(mqtt_message.topic, 0, topic_length);
   mqtt_message.payload = payload;
@@ -903,7 +914,7 @@ static uint32_t get_current_unix_time()
 }
 
 /*
- * @brief           Initializes the Device Provisioning client and generates the config for a MQTT client.
+ * @brief           Initializes the Device Provisioning client and generates the config for an MQTT client.
  * @param[in]       azure_iot          A pointer to an initialized instance of azure_iot_t.
  * @param[in]       mqtt_client_config A pointer to a generic structure to contain the configuration for
  *                                     creating and connecting an MQTT client to Azure Device Provisioning service.
@@ -912,8 +923,13 @@ static uint32_t get_current_unix_time()
  */
 static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_config_t* mqtt_client_config)
 {
-  az_span data_buffer_span, client_id_span, username_span, password_span;
-  size_t client_id_length, username_length, password_length;
+  az_span data_buffer_span;
+  az_span client_id_span;
+  az_span username_span;
+  az_span password_span;
+  size_t client_id_length;
+  size_t username_length;
+  size_t password_length;
   az_result azrc;
 
   azrc = az_iot_provisioning_client_init(
@@ -926,8 +942,8 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
 
   data_buffer_span = azure_iot->data_buffer;
   
-  password_span = az_span_split(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(password_span), RESULT_ERROR, "Failed allocating buffer for password_span.");
+  password_span = split_az_span(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(password_span), RESULT_ERROR, "Failed reserving buffer for password_span.");
 
   password_length = generate_sas_token_for_dps(
     &azure_iot->dps_client,
@@ -939,14 +955,14 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
     &azure_iot->sas_token_expiration_time);
   EXIT_IF_TRUE(password_length == 0, RESULT_ERROR, "Failed creating mqtt password for DPS connection.");    
 
-  client_id_span = az_span_split(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(client_id_span), RESULT_ERROR, "Failed allocating buffer for client_id_span.");
+  client_id_span = split_az_span(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(client_id_span), RESULT_ERROR, "Failed reserving buffer for client_id_span.");
 
   azrc = az_iot_provisioning_client_get_client_id(
       &azure_iot->dps_client, (char*)az_span_ptr(client_id_span), az_span_size(client_id_span), &client_id_length);
   EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed getting client id for DPS connection.");
 
-  username_span = az_span_split(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
+  username_span = split_az_span(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
 
   azrc = az_iot_provisioning_client_get_user_name(
       &azure_iot->dps_client, (char*)az_span_ptr(username_span), az_span_size(username_span), &username_length);
@@ -963,7 +979,7 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
 }
 
 /*
- * @brief           Initializes the Azure IoT Hub client and generates the config for a MQTT client.
+ * @brief           Initializes the Azure IoT Hub client and generates the config for an MQTT client.
  * @param[in]       azure_iot          A pointer to an initialized instance of azure_iot_t.
  * @param[in]       mqtt_client_config A pointer to a generic structure to contain the configuration for
  *                                     creating and connecting an MQTT client to Azure IoT Hub.
@@ -972,8 +988,13 @@ static int get_mqtt_client_config_for_dps(azure_iot_t* azure_iot, mqtt_client_co
  */
 static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_client_config_t* mqtt_client_config)
 {
-  az_span data_buffer_span, client_id_span, username_span, password_span;
-  size_t client_id_length, username_length, password_length;
+  az_span data_buffer_span;
+  az_span client_id_span;
+  az_span username_span;
+  az_span password_span;
+  size_t client_id_length;
+  size_t username_length;
+  size_t password_length;
   az_result azrc;
 
   azure_iot->iot_hub_client_options = az_iot_hub_client_options_default();
@@ -989,8 +1010,8 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
 
   data_buffer_span = azure_iot->data_buffer;
   
-  password_span = az_span_split(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(password_span), RESULT_ERROR, "Failed allocating buffer for password_span.");
+  password_span = split_az_span(data_buffer_span, MQTT_PASSWORD_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(password_span), RESULT_ERROR, "Failed reserving buffer for password_span.");
 
   password_length = generate_sas_token_for_iot_hub(
     &azure_iot->iot_hub_client,
@@ -1002,14 +1023,14 @@ static int get_mqtt_client_config_for_iot_hub(azure_iot_t* azure_iot, mqtt_clien
     &azure_iot->sas_token_expiration_time);
   EXIT_IF_TRUE(password_length == 0, RESULT_ERROR, "Failed creating mqtt password for IoT Hub connection.");    
 
-  client_id_span = az_span_split(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(client_id_span), RESULT_ERROR, "Failed allocating buffer for client_id_span.");
+  client_id_span = split_az_span(data_buffer_span, MQTT_CLIENT_ID_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(client_id_span), RESULT_ERROR, "Failed reserving buffer for client_id_span.");
 
   azrc = az_iot_hub_client_get_client_id(
       &azure_iot->iot_hub_client, (char*)az_span_ptr(client_id_span), az_span_size(client_id_span), &client_id_length);
   EXIT_IF_AZ_FAILED(azrc, RESULT_ERROR, "Failed getting client id for IoT Hub connection.");
 
-  username_span = az_span_split(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
+  username_span = split_az_span(data_buffer_span, MQTT_USERNAME_BUFFER_SIZE, &data_buffer_span);
 
   azrc = az_iot_hub_client_get_user_name(
       &azure_iot->iot_hub_client, (char*)az_span_ptr(username_span), az_span_size(username_span), &username_length);
@@ -1064,32 +1085,32 @@ static int generate_sas_token_for_dps(
   current_unix_time = get_current_unix_time();
   EXIT_IF_TRUE(current_unix_time == 0, 0, "Failed getting current unix time.");
 
-  *expiration_time = current_unix_time + duration_in_minutes * 60;
+  *expiration_time = current_unix_time + duration_in_minutes * NUMBER_OF_SECONDS_IN_A_MINUTE;
 
   // Step 2.a.
-  plain_sas_signature = az_span_split(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(plain_sas_signature), 0, "Failed allocating buffer for plain sas token.");
+  plain_sas_signature = split_az_span(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(plain_sas_signature), 0, "Failed reserving buffer for plain sas token.");
 
   rc = az_iot_provisioning_client_sas_get_signature(
       provisioning_client, *expiration_time, plain_sas_signature, &plain_sas_signature);
-  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key");
+  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key.");
 
   // Step 2.b.
-  sas_signature = az_span_split(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_signature), 0, "Failed allocating buffer for sas_signature.");
+  sas_signature = split_az_span(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_signature), 0, "Failed reserving buffer for sas_signature.");
   
-  decoded_sas_key = az_span_split(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(decoded_sas_key), 0, "Failed allocating buffer for decoded_sas_key.");
+  decoded_sas_key = split_az_span(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(decoded_sas_key), 0, "Failed reserving buffer for decoded_sas_key.");
 
   result = data_manipulation_functions.base64_decode(
     az_span_ptr(device_key), az_span_size(device_key), az_span_ptr(decoded_sas_key), az_span_size(decoded_sas_key), &decoded_sas_key_length);
   EXIT_IF_TRUE(result != 0, 0, "Failed decoding SAS key.");
 
   // Step 2.c.
-  sas_hmac256_signed_signature = az_span_split(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_hmac256_signed_signature), 0, "Failed allocating buffer for sas_hmac256_signed_signature.");
+  sas_hmac256_signed_signature = split_az_span(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_hmac256_signed_signature), 0, "Failed reserving buffer for sas_hmac256_signed_signature.");
 
-  result = data_manipulation_functions.hmac_sha512_encrypt(
+  result = data_manipulation_functions.hmac_sha256_encrypt(
     az_span_ptr(decoded_sas_key), decoded_sas_key_length, 
     az_span_ptr(plain_sas_signature), az_span_size(plain_sas_signature), 
     az_span_ptr(sas_hmac256_signed_signature), az_span_size(sas_hmac256_signed_signature));
@@ -1155,32 +1176,32 @@ static int generate_sas_token_for_iot_hub(
   current_unix_time = get_current_unix_time();
   EXIT_IF_TRUE(current_unix_time == 0, 0, "Failed getting current unix time.");
 
-  *expiration_time = current_unix_time + duration_in_minutes * 60;
+  *expiration_time = current_unix_time + duration_in_minutes * NUMBER_OF_SECONDS_IN_A_MINUTE;
 
   // Step 2.a.
-  plain_sas_signature = az_span_split(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(plain_sas_signature), 0, "Failed allocating buffer for plain sas token.");
+  plain_sas_signature = split_az_span(data_buffer_span, PLAIN_SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(plain_sas_signature), 0, "Failed reserving buffer for plain sas token.");
 
   rc = az_iot_hub_client_sas_get_signature(
       iot_hub_client, *expiration_time, plain_sas_signature, &plain_sas_signature);
-  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key");
+  EXIT_IF_AZ_FAILED(rc, 0, "Could not get the signature for SAS key.");
 
   // Step 2.b.
-  sas_signature = az_span_split(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_signature), 0, "Failed allocating buffer for sas_signature.");
+  sas_signature = split_az_span(data_buffer_span, SAS_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_signature), 0, "Failed reserving buffer for sas_signature.");
   
-  decoded_sas_key = az_span_split(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(decoded_sas_key), 0, "Failed allocating buffer for decoded_sas_key.");
+  decoded_sas_key = split_az_span(data_buffer_span, DECODED_SAS_KEY_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(decoded_sas_key), 0, "Failed reserving buffer for decoded_sas_key.");
 
   result = data_manipulation_functions.base64_decode(
     az_span_ptr(device_key), az_span_size(device_key), az_span_ptr(decoded_sas_key), az_span_size(decoded_sas_key), &decoded_sas_key_length);
   EXIT_IF_TRUE(result != 0, 0, "Failed decoding SAS key.");
 
   // Step 2.c.
-  sas_hmac256_signed_signature = az_span_split(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
-  EXIT_IF_TRUE(az_span_is_empty(sas_hmac256_signed_signature), 0, "Failed allocating buffer for sas_hmac256_signed_signature.");
+  sas_hmac256_signed_signature = split_az_span(data_buffer_span, SAS_HMAC256_ENCRIPTED_SIGNATURE_BUFFER_SIZE, &data_buffer_span);
+  EXIT_IF_TRUE(is_az_span_empty(sas_hmac256_signed_signature), 0, "Failed reserving buffer for sas_hmac256_signed_signature.");
 
-  result = data_manipulation_functions.hmac_sha512_encrypt(
+  result = data_manipulation_functions.hmac_sha256_encrypt(
     az_span_ptr(decoded_sas_key), decoded_sas_key_length, 
     az_span_ptr(plain_sas_signature), az_span_size(plain_sas_signature), 
     az_span_ptr(sas_hmac256_signed_signature), az_span_size(sas_hmac256_signed_signature));
@@ -1207,32 +1228,45 @@ static int generate_sas_token_for_iot_hub(
   return mqtt_password_length;
 }
 
+/**
+ * @brief        Generates a custom payload for DPS registration request containing the Azure PnP model ID.
+ * @remark       This payload with the model ID is required for Azure IoT Central to properly
+ *               assign the IoT Plug and Play template.
+ * 
+ * @param[in]    mode_id        The string with the IoT Plug and Play model ID.
+ * @param[in]    data_buffer    Buffer where to write the resulting payload.
+ * @param[in]    remainder      The remainder space of `data_buffer` after enough is reserved for
+ *                              the resulting payload. 
+ * 
+ * @return       az_span        An az_span (reserved from `data_buffer`) containing the payload
+ *                              for the DPS registration request.
+ */
 static az_span generate_dps_register_custom_property(az_span model_id, az_span data_buffer, az_span* remainder)
 {
   az_span custom_property;
   size_t length = lengthof(DPS_REGISTER_CUSTOM_PAYLOAD_BEGIN) + az_span_size(model_id) + lengthof(DPS_REGISTER_CUSTOM_PAYLOAD_END);
       
-  custom_property = az_span_split(data_buffer, length, remainder);
-  EXIT_IF_TRUE(az_span_is_empty(custom_property), AZ_SPAN_EMPTY, "Failed generating DPS register custom property.");
+  custom_property = split_az_span(data_buffer, length, remainder);
+  EXIT_IF_TRUE(is_az_span_empty(custom_property), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (not enough space).");
 
   data_buffer = az_span_copy(data_buffer, AZ_SPAN_FROM_STR(DPS_REGISTER_CUSTOM_PAYLOAD_BEGIN));
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (prefix).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (prefix).");
   
   data_buffer = az_span_copy(data_buffer, model_id);
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (model id).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (model id).");
   
   data_buffer = az_span_copy(data_buffer, AZ_SPAN_FROM_STR(DPS_REGISTER_CUSTOM_PAYLOAD_END));
-  EXIT_IF_TRUE(az_span_is_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (suffix).");
+  EXIT_IF_TRUE(is_az_span_empty(data_buffer), AZ_SPAN_EMPTY, "Failed generating DPS register custom property (suffix).");
   
   return custom_property;
 }
 
 /* --- az_core extensions --- */
-az_span az_span_split(az_span span, int32_t size, az_span* remainder)
+az_span split_az_span(az_span span, int32_t size, az_span* remainder)
 {
   az_span result = az_span_slice(span, 0, size);
 
-  if (remainder != NULL && !az_span_is_empty(result))
+  if (remainder != NULL && !is_az_span_empty(result))
   {
     *remainder = az_span_slice(span, size, az_span_size(span));
   }
@@ -1240,16 +1274,16 @@ az_span az_span_split(az_span span, int32_t size, az_span* remainder)
   return result;
 }
 
-az_span az_span_slice_and_copy(az_span destination, az_span source, az_span* remainder)
+az_span slice_and_copy_az_span(az_span destination, az_span source, az_span* remainder)
 {
-  az_span result = az_span_split(destination, az_span_size(source), remainder);
+  az_span result = split_az_span(destination, az_span_size(source), remainder);
 
-  if (az_span_is_empty(*remainder))
+  if (is_az_span_empty(*remainder))
   {
     result = AZ_SPAN_EMPTY;
   }
 
-  if (!az_span_is_empty(result))
+  if (!is_az_span_empty(result))
   {
     (void)az_span_copy(result, source);
   }
diff --git a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.h b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.h
index a7a48e4..4cf5221 100644
--- a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.h
+++ b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/AzureIoT.h
@@ -2,8 +2,10 @@
 // SPDX-License-Identifier: MIT
 
 /*
- * AzureIoT.cpp contains a state machine that implements those steps, plus abstractions to simplify
- * its overall use. Besides the basic configuration needed to access the Azure IoT services,
+ * AzureIoT.cpp contains a state machine that implements the necessary calls to azure-sdk-for-c
+ * for aiding to connect and work with Azure IoT services, plus abstractions to
+ * simplify overall use of azure-sdk-for-c.
+ * Besides the basic configuration needed to access the Azure IoT services,
  * all that is needed is to provide the functions required by that layer to:
  * - Interact with your MQTT client,
  * - Perform data manipulations (HMAC SHA256 encryption, Base64 decoding and encoding),
@@ -57,13 +59,13 @@ extern log_function_t default_logging_function;
 #endif // DISABLE_LOGGING
 
 
-/* --- Azure Abstraction --- */
+/* --- Azure Definitions --- */
 #define DPS_GLOBAL_ENDPOINT_FQDN          "global.azure-devices-provisioning.net"
-#define DPS_GLOBAL_ENDPOINT_PORT          8883
-#define IOT_HUB_ENDPOINT_PORT             8883
+#define DPS_GLOBAL_ENDPOINT_PORT          AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
+#define IOT_HUB_ENDPOINT_PORT             AZ_IOT_DEFAULT_MQTT_CONNECT_PORT
 
 #define DEFAULT_SAS_TOKEN_LIFETIME_IN_MINUTES 60
-#define SAS_TOKEN_REFRESH_THRESHOLD_SECS 30 
+#define SAS_TOKEN_REFRESH_THRESHOLD_IN_SECS 30 
 
 /*
  * The structures below define a generic interface to abstract the interaction of this module, 
@@ -83,12 +85,13 @@ typedef enum mqtt_qos_t_enum
 mqtt_qos_t;
 
 /*
- * @brief     Defines a generic MQTT message to be exchanged between the AzureIoT.h layer
+ * @brief     Defines a generic MQTT message to be exchanged between the AzureIoT layer
  *            and the user application. 
  * @remark    It uses azure-sdk-for-c's az_span construct, which is merely a structure that
  *            has a pointer to a buffer and its size. Messages without a payload will have
  *            the `payload` member set to AZ_SPAN_EMPTY.
- *            Please see the az_span.h in azure-sdk-for-c for more details.
+ *            Please see the az_span.h in azure-sdk-for-c for more details at
+ *            https://azuresdkdocs.blob.core.windows.net/$web/c/az_core/1.2.0/az__span_8h.html
  */
 typedef struct mqtt_message_t_struct
 {
@@ -105,12 +108,12 @@ mqtt_message_t;
 typedef struct mqtt_client_config_t_struct
 {
   /*
-   * @brief    FQDN address of the broker the MQTT client shall connect to.
+   * @brief    FQDN address of the broker that the MQTT client shall connect to.
    */
   az_span address;
 
   /*
-   * @brief    Port of the broker the MQTT client shall connect to.
+   * @brief    Port of the broker that the MQTT client shall connect to.
    */
   int port;
 
@@ -133,12 +136,12 @@ mqtt_client_config_t;
 
 /*
  * @brief    Generic pointer to the actual instance of the application MQTT client.
- * @remark   set by the user application when the `mqtt_client_init_function_t` calback is invoked.
+ * @remark   set by the user application when the `mqtt_client_init_function_t` callback is invoked.
  */
 typedef void* mqtt_client_handle_t;
 
 /*
- * @brief         Function to initialize and connect a MQTT client.
+ * @brief         Function to initialize and connect an MQTT client.
  * @remark        When this function is called, it provides the information necessary to initialize a 
  *                specific MQTT client (whichever is used by the user application). In this callback
  *                it is expected that the MQTT client will be created/initialized, started and that it
@@ -155,7 +158,7 @@ typedef void* mqtt_client_handle_t;
 typedef int (*mqtt_client_init_function_t)(mqtt_client_config_t* mqtt_client_config, mqtt_client_handle_t* mqtt_client_handle);
 
 /*
- * @brief        Function to disconnect and deinitialize a MQTT client.
+ * @brief        Function to disconnect and deinitialize an MQTT client.
  * @remark       When this function is called the MQTT client instance referenced by `mqtt_client_handle` shall disconnect
  *               from the server and any functions of the MQTT client API that destroy the instance shall be called
  *               (so any allocated memory resources can be released).
@@ -193,10 +196,8 @@ typedef int (*mqtt_client_publish_function_t)(mqtt_client_handle_t mqtt_client_h
  *               `mqtt_client_handle`) to invoke the appropriate function in the MQTT client API to subscribe to 
  *               an MQTT topic.
  *
- * @param[in]    topic           The string containing the complete MQTT topic name to subscribed to.
+ * @param[in]    topic           The az_span with the string containing the complete MQTT topic name to subscribed to.
  *                               This string is always NULL-terminated.
- * @param[in]    topic_length    The length of `topic`. It can be used in case the MQTT client takes a 
- *                               topic name as a non-NULL-terminated string.
  * @param[in]    qos             MQTT QoS to be used for the topic subscription.
  * 
  *
@@ -204,7 +205,7 @@ typedef int (*mqtt_client_publish_function_t)(mqtt_client_handle_t mqtt_client_h
  *                               Azure IoT client expects `azure_iot_mqtt_client_subscribe_completed` to be called once the
  *                               MQTT client receives a SUBACK.
  */
-typedef int (*mqtt_client_subscribe_function_t)(mqtt_client_handle_t mqtt_client_handle, const uint8_t* topic, size_t topic_lenght, mqtt_qos_t qos);
+typedef int (*mqtt_client_subscribe_function_t)(mqtt_client_handle_t mqtt_client_handle, az_span topic, mqtt_qos_t qos);
 
 /*
  * @brief    Structure that consolidates all the abstracted MQTT functions.
@@ -213,13 +214,13 @@ typedef struct mqtt_client_interface_t_struct
 {
   mqtt_client_init_function_t mqtt_client_init;
   mqtt_client_deinit_function_t mqtt_client_deinit;
-  mqtt_client_subscribe_function_t mqtt_client_subscribe;
   mqtt_client_publish_function_t mqtt_client_publish;
+  mqtt_client_subscribe_function_t mqtt_client_subscribe;
 }
 mqtt_client_interface_t;
 
 /*
- * @brief    This function must be provided by the user for the AzureIoT.h layer
+ * @brief    This function must be provided by the user for the AzureIoT layer
  *           to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]     data              Buffer containing the Base64-encoded content.
@@ -234,14 +235,14 @@ mqtt_client_interface_t;
 typedef int (*base64_decode_function_t)(uint8_t* data, size_t data_length, uint8_t* decoded, size_t decoded_size, size_t* decoded_length);
 
 /*
- * @brief         This function must be provided by the user for the AzureIoT.h layer
+ * @brief         This function must be provided by the user for the AzureIoT layer
  *                to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]     data              Buffer containing the Base64-decoded content.
  * @param[in]     data_length       Length of `data`.
- * @param[in]     decoded           Buffer where to write the Base64-encoded content of `data`.
- * @param[in]     decoded_size      Size of `encoded`.
- * @param[out]    decoded_length    The final length of the Base64-encoded content written in 
+ * @param[in]     encoded           Buffer where to write the Base64-encoded content of `data`.
+ * @param[in]     encoded_size      Size of `encoded`.
+ * @param[out]    encoded_length    The final length of the Base64-encoded content written in 
  *                                  the `encoded` buffer.
  * 
  * @return        int               0 on success, or non-zero if any failure occurs.
@@ -249,19 +250,19 @@ typedef int (*base64_decode_function_t)(uint8_t* data, size_t data_length, uint8
 typedef int (*base64_encode_function_t)(uint8_t* data, size_t data_length, uint8_t* encoded, size_t encoded_size, size_t* encoded_length);
 
 /*
- * @brief        This function must be provided by the user for the AzureIoT.h layer
+ * @brief        This function must be provided by the user for the AzureIoT layer
  *               to perform the generation of the SAS tokens used as MQTT passwords.
  * 
  * @param[in]    key                       Encryption key to be used in the HMAC-SHA256 algorithm.
  * @param[in]    key_length                Length of `key`.
  * @param[in]    payload                   Buffer containing the data to be encrypted.
  * @param[in]    payload_size              Size of `payload`.
- * @param[in]    encrypted_payload         Buffer where to write teh HMAC-SHA256 encrypted content of `payload`.
+ * @param[in]    encrypted_payload         Buffer where to write the HMAC-SHA256 encrypted content of `payload`.
  * @param[in]    encrypted_payload_size    The size of the `encrypted_payload` buffer.
  * 
  * @return       int                       0 on success, or non-zero if any failure occurs.
  */
-typedef int (*hmac_sha512_encryption_function_t)(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* encrypted_payload, size_t encrypted_payload_size);
+typedef int (*hmac_sha256_encryption_function_t)(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* encrypted_payload, size_t encrypted_payload_size);
 
 /*
  * @brief    Structure that consolidates all the data manipulation functions.
@@ -270,7 +271,7 @@ typedef struct data_manipulation_functions_t_struct
 {
   base64_decode_function_t base64_decode;
   base64_encode_function_t base64_encode;
-  hmac_sha512_encryption_function_t hmac_sha512_encrypt;
+  hmac_sha256_encryption_function_t hmac_sha256_encrypt;
 }
 data_manipulation_functions_t;
 
@@ -295,7 +296,7 @@ typedef void (*properties_update_completed_t)(uint32_t request_id, az_iot_status
 typedef void (*properties_received_t)(az_span properties);
 
 /*
- * @brief    Structure containing all the details of a Azure Plug and Play Command.
+ * @brief    Structure containing all the details of a IoT Plug and Play Command.
  */
 typedef struct command_request_t_struct
 {
@@ -323,7 +324,7 @@ typedef struct command_request_t_struct
 command_request_t;
 
 /*
- * @brief        Defines the callback for receiving an Azure Plug-and-Play Command.
+ * @brief        Defines the callback for receiving an IoT Plug and Play Command.
  * @remark       A response for this command MUST be provided to Azure by calling 
  *               `azure_iot_send_command_response`.
  * 
@@ -335,7 +336,7 @@ command_request_t;
 typedef void (*command_request_received_t)(command_request_t command);
 
 /*
- * @brief    All the possible status returned by `azure_iot_get_status`.
+ * @brief    All the possible statuses returned by `azure_iot_get_status`.
  */
 typedef enum azure_iot_status_t_struct
 {
@@ -407,7 +408,7 @@ azure_iot_client_state_t;
  *           Also make sure that the instance of `azure_iot_config_t` (and its members) do not
  *           lose scope throughout the lifetime of the Azure IoT client.
  *           Most of the members of this structure use az_span for encapsulating a buffer and
- *           its size. For more details on az_span, please explorer the code at 
+ *           its size. For more details on az_span, please explore the code at 
  *           https://github.com/azure/azure-sdk-for-c.
  */
 typedef struct azure_iot_config_t_struct
@@ -447,8 +448,8 @@ typedef struct azure_iot_config_t_struct
   az_span device_id;
 
   /*
-   * @brief     Symetric key of the device to authenticate as when connecting to Azure IoT Hub.
-   * @remark    This key will be used to generate the MQTT client password, is using SAS-token
+   * @brief     Symmetric key of the device to authenticate as when connecting to Azure IoT Hub.
+   * @remark    This key will be used to generate the MQTT client password, if using SAS-token
    *            authentication (which is used, for example, when connecting to Azure IoT Central).
    */
   az_span device_key;
@@ -456,7 +457,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     The "Registration ID" to authenticate with when connecting to
    *            Azure Device Provisioning service.
-   * @remark    This information only when performing device-provisioning (which is used,
+   * @remark    This information is only needed when performing device-provisioning (which is used,
                 for example, when connecting to Azure IoT Central). If device-provisioning is
                 not being used (i.e., Azure IoT client is connecting directly to Azure IoT Hub)
                 this member MUST be set with AZ_SPAN_EMPTY.
@@ -468,7 +469,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     The "ID Scope" to authenticate with when connecting to
    *            Azure Device Provisioning service.
-   * @remark    This information only when performing device-provisioning (which is used,
+   * @remark    This information is only needed when performing device-provisioning (which is used,
                 for example, when connecting to Azure IoT Central). If device-provisioning is
                 not being used (i.e., Azure IoT client is connecting directly to Azure IoT Hub)
                 this member MUST be set with AZ_SPAN_EMPTY.
@@ -476,8 +477,8 @@ typedef struct azure_iot_config_t_struct
   az_span dps_id_scope;
 
   /*
-   * @brief     Model ID of the Azure Plug-and-Play template implemented by the user application.
-   * @remark    This is used only when the application uses/implements Azure IoT Plug-and-Play.
+   * @brief     Model ID of the IoT Plug and Play template implemented by the user application.
+   * @remark    This is used only when the application uses/implements IoT Plug and Play.
    */
   az_span model_id;
 
@@ -533,9 +534,9 @@ typedef struct azure_iot_config_t_struct
 
   /*
    * @brief    Amount of minutes for which the MQTT password should be valid.
-   * @remark   If set to zero, Azure Iot client sets it to the default value of 60 minutes.
+   * @remark   If set to zero, Azure IoT client sets it to the default value of 60 minutes.
    *           Once this amount of minutes has passed and the MQTT password is expired,
-   *           Azure IoT client trigers its logic to generate a new password and reconnect with
+   *           Azure IoT client triggers its logic to generate a new password and reconnect with
    *           Azure IoT Hub.
    */
   uint32_t sas_token_lifetime_in_minutes;
@@ -543,7 +544,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     Callback handler used by Azure IoT client to inform the user application of
    *            a completion of properties update.
-   * @remark    A properties update is trigered by the user application when
+   * @remark    A properties update is triggered by the user application when
    *            `azure_iot_send_properties_update` is called.
    */
   properties_update_completed_t on_properties_update_completed;
@@ -551,7 +552,7 @@ typedef struct azure_iot_config_t_struct
   /*
    * @brief     Callback handler used by Azure IoT client to inform the user application of
    *            a writable-properties update received from Azure IoT Hub.
-   * @remark    If Azure IoT Plug.-and-Play is used, a response must be sent back to
+   * @remark    If IoT Plug and Play is used, a response must be sent back to
    *            Azure IoT Hub.
    */
   properties_received_t on_properties_received;
@@ -590,7 +591,7 @@ typedef struct azure_iot_t_struct
 azure_iot_t;
 
 /*
- * @brief        Initialies the azure_iot_t structure that holds the Azure IoT client state.
+ * @brief        Initializes the azure_iot_t structure that holds the Azure IoT client state.
  * @remark       This function must be called only once per `azure_iot_t` instance,
  *               before any other function can be called using it.
  * 
@@ -598,9 +599,9 @@ azure_iot_t;
  * @param[in]    azure_iot_config    A pointer to a `azure_iot_config_t` containing all the
  *                                   configuration neeeded for the client to connect and work with
  *                                   the Azure IoT services.
- * @return       int                 0 on success, or non-zero if any failure occurs.
+ * @return                           Nothing.
  */
-int azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config);
+void azure_iot_init(azure_iot_t* azure_iot, azure_iot_config_t* azure_iot_config);
 
 /*
  * @brief        Starts an Azure IoT client.
@@ -673,23 +674,23 @@ void azure_iot_do_work(azure_iot_t* azure_iot);
 int azure_iot_send_telemetry(azure_iot_t* azure_iot, az_span message);
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief        Sends a property update message to Azure IoT Hub.
  *
- * @param[in]    azure_iot                         The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
- * @param[in]    message                           An `az_span` with the message with the reported properties update
- *                                                 (a JSON document formatted according to the DTDL specification).
- *                                                 `message` gets passed as-is to the MQTT client publish function as the payload, so if 
- *                                                 your MQTT client expects a null-terminated string for payload, make sure `message` is
- *                                                 a null-terminated string.
- * @param[in]    request_id                        An unique identification number to correlate the response with when
- *                                                 `on_properties_update_completed` (set in azure_iot_config_t) is invoked.
+ * @param[in]    azure_iot     The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
+ * @param[in]    request_id    An unique identification number to correlate the response with when
+ * @param[in]    message       An `az_span` with the message with the reported properties update
+ *                             (a JSON document formatted according to the DTDL specification).
+ *                             `message` gets passed as-is to the MQTT client publish function as the payload, so if 
+ *                             your MQTT client expects a null-terminated string for payload, make sure `message` is
+ *                             a null-terminated string.
+ *                             `on_properties_update_completed` (set in azure_iot_config_t) is invoked.
  *
- * @return       int                               0 if the function succeeds, or non-zero if any failure occurs.
+ * @return       int           0 if the function succeeds, or non-zero if any failure occurs.
  */
 int azure_iot_send_properties_update(azure_iot_t* azure_iot, uint32_t request_id, az_span message);
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief        Sends a property update message to Azure IoT Hub.
  *
  * @param[in]    azure_iot          The pointer to the azure_iot_t instance that holds the state of the Azure IoT client.
  * @param[in]    request_id         The same `request_id` of the device command received from Azure IoT Hub.
@@ -720,7 +721,7 @@ int azure_iot_mqtt_client_connected(azure_iot_t* azure_iot);
 /*
  * @brief        Informs the Azure IoT client that the MQTT client is disconnected.
  * @remark       This must be called after Azure IoT client invokes the `mqtt_client_deinit` callback
- *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has disconencted
+ *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has disconnected
  *               from the Azure IoT service.
  * 
  * @param[in]    azure_iot    A pointer to the instance of `azure_iot_t` previously initialized by the caller.
@@ -746,7 +747,7 @@ int azure_iot_mqtt_client_subscribe_completed(azure_iot_t* azure_iot, int packet
  * @brief        Informs the Azure IoT client that the MQTT client has completed a PUBLISH.
  * @remark       This must be called after Azure IoT client invokes the `mqtt_client_publish` callback
  *               (provided in the azure_iot_config_t instance) so it knows the MQTT client has
- *               completed a MQTT PUBLISH. If the QoS is 0 (AT MOST ONCE), this shall be called by 
+ *               completed an MQTT PUBLISH. If the QoS is 0 (AT MOST ONCE), this shall be called by 
  *               the user application right after `mqtt_client_publish` is invoked. If the QoS of
  *               is 1 (AT LEAST ONCE), this shall be called whenever a PUBACK is received.
  * 
@@ -776,13 +777,13 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
  */
 
 /**
- * @brief Checks whether `span` is equal AZ_SPAN_EMPTY.
+ * @brief Checks whether `span` is equal to AZ_SPAN_EMPTY.
  *
  * @param[in]    span           A span to be verified.
  *
  * @return       boolean        True if `span`'s pointer and size are equal to AZ_SPAN_EMPTY, or false otherwise.
  */
-#define az_span_is_empty(span) az_span_is_content_equal(span, AZ_SPAN_EMPTY)
+#define is_az_span_empty(span) az_span_is_content_equal(span, AZ_SPAN_EMPTY)
 
 /**
  * @brief Slices `span` at position `size`, returns the first slice and assigns the second slice to `remainder`.
@@ -793,7 +794,7 @@ int azure_iot_mqtt_client_message_received(azure_iot_t* azure_iot, mqtt_message_
  *
  * @return       az_span        A slice of `span` from position zero to `size`.
  */
-az_span az_span_split(az_span span, int32_t size, az_span* remainder);
+az_span split_az_span(az_span span, int32_t size, az_span* remainder);
 
 /**
  * @brief Slices `destination` to fit `source`, copy `source` into the first slice and returns the second through `remainder`.
@@ -804,6 +805,6 @@ az_span az_span_split(az_span span, int32_t size, az_span* remainder);
  *
  * @return       az_span        A slice of `destination` with the same size as `source`, with `source`'s content copied over.
  */
-static az_span az_span_slice_and_copy(az_span destination, az_span source, az_span* remainder);
+static az_span slice_and_copy_az_span(az_span destination, az_span source, az_span* remainder);
 
 #endif // AZURE_IOT_H
diff --git a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_Central_ESP32_AzureIoTKit.ino b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_Central_ESP32_AzureIoTKit.ino
index 92df1b9..f096627 100644
--- a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_Central_ESP32_AzureIoTKit.ino
+++ b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_Central_ESP32_AzureIoTKit.ino
@@ -12,9 +12,9 @@
  * It uses our Azure Embedded SDK for C to help interact with Azure IoT.
  * For reference, please visit https://github.com/azure/azure-sdk-for-c and https://azureiotcentral.com/.
  * 
- * To connect and work with Azure IoT Hub you need a MQTT client, connecting, subscribing
+ * To connect and work with Azure IoT Hub you need an MQTT client, connecting, subscribing
  * and publishing to specific topics to use the messaging features of the hub.
- * Our azure-sdk-for-c is a MQTT client support library, helping composing and parsing the
+ * Our azure-sdk-for-c is an MQTT client support library, helping composing and parsing the
  * MQTT topic names and messages exchanged with the Azure IoT Hub.
  * 
  * The additional layers in this sketch provide a structured use of azure-sdk-for-c and
@@ -28,7 +28,7 @@
  * - Perform data manipulations (HMAC SHA256 encryption, Base64 decoding and encoding),
  * - Receive the callbacks for Plug and Play properties and commands.
  * 
- * Azure_IoT_PnP_Template.cpp contains the actual implementation of the Azure Plug-and-Play template
+ * Azure_IoT_PnP_Template.cpp contains the actual implementation of the IoT Plug and Play template
  * specific for the Espressif ESP32 Azure IoT Kit board.
  * 
  * To properly connect to your Azure IoT services, please fill the information in the `iot_configs.h` file. 
@@ -203,13 +203,13 @@ static int mqtt_client_deinit_function(mqtt_client_handle_t mqtt_client_handle)
 /*
  * See the documentation of `mqtt_client_subscribe_function_t` in AzureIoT.h for details.
  */
-static int mqtt_client_subscribe_function(mqtt_client_handle_t mqtt_client_handle, const uint8_t* topic, size_t topic_length, mqtt_qos_t qos)
+static int mqtt_client_subscribe_function(mqtt_client_handle_t mqtt_client_handle, az_span topic, mqtt_qos_t qos)
 {
-  LogInfo("MQTT client subscribing to '%s'", topic);
+  LogInfo("MQTT client subscribing to '%.*s'", az_span_size(topic), az_span_ptr(topic));
        
   // As per documentation, `topic` always ends with a null-terminator.
   // esp_mqtt_client_subscribe returns the packet id or negative on error already, so no conversion is needed.
-  int packet_id = esp_mqtt_client_subscribe((esp_mqtt_client_handle_t)mqtt_client_handle, (const char*)topic, (int)qos);
+  int packet_id = esp_mqtt_client_subscribe((esp_mqtt_client_handle_t)mqtt_client_handle, (const char*)az_span_ptr(topic), (int)qos);
 
   return packet_id;
 }
@@ -242,7 +242,7 @@ static int mqtt_client_publish_function(mqtt_client_handle_t mqtt_client_handle,
 /* --- Other Interface functions required by Azure IoT --- */
 
 /*
- * See the documentation of `hmac_sha512_encryption_function_t` in AzureIoT.h for details.
+ * See the documentation of `hmac_sha256_encryption_function_t` in AzureIoT.h for details.
  */
 static int mbedtls_hmac_sha256(const uint8_t* key, size_t key_length, const uint8_t* payload, size_t payload_length, uint8_t* signed_payload, size_t signed_payload_size)
 {
@@ -330,7 +330,7 @@ void setup()
 
   /* 
    * The configuration structure used by Azure IoT must remain unchanged (including data buffer) 
-   * throughout the lifetime of the sample. This variable must also not loose context so other
+   * throughout the lifetime of the sample. This variable must also not lose context so other
    * components do not overwrite any information within this structure.
    */
   azure_iot_config.user_agent = AZ_SPAN_FROM_STR(AZURE_SDK_CLIENT_USER_AGENT_WORKAROUND);
@@ -347,22 +347,17 @@ void setup()
   azure_iot_config.mqtt_client_interface.mqtt_client_deinit = mqtt_client_deinit_function;
   azure_iot_config.mqtt_client_interface.mqtt_client_subscribe = mqtt_client_subscribe_function;
   azure_iot_config.mqtt_client_interface.mqtt_client_publish = mqtt_client_publish_function;
-  azure_iot_config.data_manipulation_functions.hmac_sha512_encrypt = mbedtls_hmac_sha256;
+  azure_iot_config.data_manipulation_functions.hmac_sha256_encrypt = mbedtls_hmac_sha256;
   azure_iot_config.data_manipulation_functions.base64_decode = base64_decode;
   azure_iot_config.data_manipulation_functions.base64_encode = base64_encode;
   azure_iot_config.on_properties_update_completed = on_properties_update_completed;
   azure_iot_config.on_properties_received = on_properties_received;
   azure_iot_config.on_command_request_received = on_command_request_received;
 
-  if (azure_iot_init(&azure_iot, &azure_iot_config) != 0)
-  {
-    LogError("Failed initializing the Azure IoT client.");
-  }
-  else
-  {
-    LogInfo("Azure IoT client initialized (state=%d)", azure_iot.state);
-    azure_iot_start(&azure_iot);
-  }
+  azure_iot_init(&azure_iot, &azure_iot_config);
+  azure_iot_start(&azure_iot);
+
+  LogInfo("Azure IoT client initialized (state=%d)", azure_iot.state);
 }
 
 void loop()
@@ -451,7 +446,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
     int i, r;
 
     case MQTT_EVENT_ERROR:
-     LogError("MQTT client in ERROR state.");
+      LogError("MQTT client in ERROR state.");
       LogError( 
         "esp_tls_stack_err=%d; esp_tls_cert_verify_flags=%d;esp_transport_sock_errno=%d;error_type=%d;connect_return_code=%d",  
         event->error_handle->esp_tls_stack_err,
@@ -481,7 +476,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
           LogError("connect_return_code=MQTT_CONNECTION_REFUSE_NOT_AUTHORIZED"); 
           break; 
         default: 
-          LogError("connect_return_code=unknown"); 
+          LogError("connect_return_code=unknown (%d)", event->error_handle->connect_return_code); 
           break; 
       };
 
@@ -543,7 +538,7 @@ static esp_err_t esp_mqtt_event_handler(esp_mqtt_event_handle_t event)
       LogInfo("MQTT client connecting.");
       break;
     default:
-      LogError("MQTT event UNKNOWN");
+      LogError("MQTT event UNKNOWN.");
       break;
   }
 
diff --git a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.cpp b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.cpp
index d62922a..fe378aa 100644
--- a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.cpp
+++ b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.cpp
@@ -86,7 +86,7 @@ static uint32_t telemetry_send_count = 0;
 static size_t telemetry_frequency_in_seconds = 10; // With default frequency of once in 10 seconds.
 static time_t last_telemetry_send_time = INDEFINITE_TIME;
 
-#define OLED_SPLASH_MESSAGE              "Espressif ESP32 Azure IoT Kit + Azure IoT Central"
+#define OLED_SPLASH_MESSAGE              "Espressif ESP32 Azure IoT Kit + Central"
 
 static bool led1_on = false;
 static bool led2_on = false;
@@ -109,6 +109,9 @@ void azure_pnp_init()
 
   esp32_azureiotkit_oled_clean_screen();
   esp32_azureiotkit_oled_show_message((uint8_t*)OLED_SPLASH_MESSAGE, lengthof(OLED_SPLASH_MESSAGE));
+
+  esp32_azureiotkit_led1_set_state(LED_STATE_OFF);
+  esp32_azureiotkit_led2_set_state(LED_STATE_OFF);
 }
 
 const az_span azure_pnp_get_model_id()
@@ -216,7 +219,7 @@ int azure_pnp_handle_properties_update(azure_iot_t* azure_iot, az_span propertie
   size_t length;
 
   result = consume_properties_and_generate_response(azure_iot, properties, data_buffer, DATA_BUFFER_SIZE, &length);
-  EXIT_IF_TRUE(result != RESULT_OK, RESULT_ERROR, "Failed generating properties ack payload.");
+  EXIT_IF_TRUE(result != RESULT_OK, RESULT_ERROR, "Failed consuming/generating properties ack payload.");
 
   result = azure_iot_send_properties_update(azure_iot, request_id, az_span_create(data_buffer, length));
   EXIT_IF_TRUE(result != RESULT_OK, RESULT_ERROR, "Failed sending reported properties update.");
@@ -322,7 +325,7 @@ static int generate_telemetry_payload(uint8_t* payload_buffer, size_t payload_bu
 
   if ((payload_buffer_size - az_span_size(payload_buffer_span)) < 1)
   {
-    LogError("Insuficient space for telemetry payload null terminator.");
+    LogError("Insufficient space for telemetry payload null terminator.");
     return RESULT_ERROR;
   }
 
@@ -399,7 +402,7 @@ static int generate_device_info_payload(az_iot_hub_client const* hub_client, uin
 
   if ((payload_buffer_size - az_span_size(payload_buffer_span)) < 1)
   {
-    LogError("Insuficient space for telemetry payload null terminator.");
+    LogError("Insufficient space for telemetry payload null terminator.");
     return RESULT_ERROR;
   }
 
@@ -497,8 +500,9 @@ static int consume_properties_and_generate_response(
     }
     else
     {
-      LogError("Unexpected property received (%.*s)",
+      LogError("Unexpected property received (%.*s).",
         az_span_size(jr.token.slice), az_span_ptr(jr.token.slice));
+        return RESULT_ERROR;
     }
 
     azrc = az_json_reader_next_token(&jr);
diff --git a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.h b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.h
index b9db855..c8e5284 100644
--- a/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.h
+++ b/examples/Azure_IoT_Central_ESP32_AzureIoTKit/Azure_IoT_PnP_Template.h
@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: MIT
 
 /*
- * Azure_IoT_PnP_Template.cpp implements the the Azure Plug-and-Play template
+ * Azure_IoT_PnP_Template.cpp implements the IoT Plug and Play template
  * specific for the Espressif ESP32 Azure IoT Kit board.
  */
  
@@ -19,8 +19,8 @@
 void azure_pnp_init();
 
 /*
- * @brief     Returns the model id of the Azure Plug and Play template implemented by this module.
- * @remark    Every Azure Plug and Play template has a model id that must be informed by the 
+ * @brief     Returns the model id of the IoT Plug and Play template implemented by this device.
+ * @remark    Every IoT Plug and Play template has a model id that must be informed by the 
  *            device during Azure IoT provisioning and connection with the Azure IoT Hub.
  * @return    az_span       An `az_span` containing the model id implemented by this module.
  */
@@ -52,12 +52,12 @@ int azure_pnp_send_device_info(azure_iot_t* azure_iot, uint32_t request_id);
 void azure_pnp_set_telemetry_frequency(size_t frequency_in_seconds);
 
 /*
- * @brief     Sends telemetry implemented by this Azure Plug and Play application to Azure IoT Central.
- * @remark    The Azure Plug and Play template implemented by this module is specific to the
+ * @brief     Sends telemetry implemented by this IoT Plug and Play application to Azure IoT Central.
+ * @remark    The IoT Plug and Play template implemented by this device is specific to the
  *            Espressif ESP32 Azure IoT Kit board, which contains several sensors.
  *            The template defines telemetry data points for temperature, humidity, 
  *            pressure, altitude, luminosity, magnetic field, rolling and pitch angles, 
- *            as well as acceleration. All of these data is read from the board sensors and sent to 
+ *            as well as acceleration. All of these data are read from the board sensors and sent to 
  *            Azure IoT Central when `azure_pnp_send_telemetry` is called.
  *            This function must be called frequently enough, no slower than the frequency set
  *            with `azure_pnp_set_telemetry_frequency` (or the default frequency of 10 seconds).
@@ -72,7 +72,7 @@ int azure_pnp_send_telemetry(azure_iot_t* azure_iot);
 /*
  * @brief     Handles a command when it is received from Azure IoT Central.
  * @remark    This function will perform the task requested by the command received 
- *            (if the command matches the expected name) and send back a response to 
+ *            (if the command matches the expected name) and sends back a response to 
  *            Azure IoT Central.
  *
  * @param[in]    azure_iot          A pointer to a azure_iot_t instance, previously initialized 
diff --git a/examples/Azure_IoT_Hub_ESP32/AzIoTSasToken.cpp b/examples/Azure_IoT_Hub_ESP32/AzIoTSasToken.cpp
index 2541539..3cdc2f7 100644
--- a/examples/Azure_IoT_Hub_ESP32/AzIoTSasToken.cpp
+++ b/examples/Azure_IoT_Hub_ESP32/AzIoTSasToken.cpp
@@ -12,7 +12,7 @@
 
 #define INDEFINITE_TIME ((time_t)-1)
 
-#define az_span_is_empty(x) (az_span_size(x) == az_span_size(AZ_SPAN_EMPTY) && az_span_ptr(x) == az_span_ptr(AZ_SPAN_EMPTY))
+#define is_az_span_empty(x) (az_span_size(x) == az_span_size(AZ_SPAN_EMPTY) && az_span_ptr(x) == az_span_ptr(AZ_SPAN_EMPTY))
 
 static uint32_t getSasTokenExpiration(const char* sasToken)
 {
@@ -242,7 +242,7 @@ int AzIoTSasToken::Generate(unsigned int expiryTimeInMinutes)
       expiryTimeInMinutes,
       this->sasTokenBuffer);
   
-  if (az_span_is_empty(this->sasToken))
+  if (is_az_span_empty(this->sasToken))
   {
     Logger.Error("Failed generating SAS token");
     return 1;
diff --git a/examples/Azure_IoT_Hub_ESP32/Azure_IoT_Hub_ESP32.ino b/examples/Azure_IoT_Hub_ESP32/Azure_IoT_Hub_ESP32.ino
index fd47ba9..9cd0a60 100644
--- a/examples/Azure_IoT_Hub_ESP32/Azure_IoT_Hub_ESP32.ino
+++ b/examples/Azure_IoT_Hub_ESP32/Azure_IoT_Hub_ESP32.ino
@@ -6,9 +6,9 @@
  * It uses our Azure Embedded SDK for C to help interact with Azure IoT.
  * For reference, please visit https://github.com/azure/azure-sdk-for-c.
  * 
- * To connect and work with Azure IoT Hub you need a MQTT client, connecting, subscribing
+ * To connect and work with Azure IoT Hub you need an MQTT client, connecting, subscribing
  * and publishing to specific topics to use the messaging features of the hub.
- * Our azure-sdk-for-c is a MQTT client support library, helping composing and parsing the
+ * Our azure-sdk-for-c is an MQTT client support library, helping composing and parsing the
  * MQTT topic names and messages exchanged with the Azure IoT Hub.
  *
  * This sample performs the following tasks:
@@ -64,7 +64,7 @@ static const char* password = IOT_CONFIG_WIFI_PASSWORD;
 static const char* host = IOT_CONFIG_IOTHUB_FQDN;
 static const char* mqtt_broker_uri = "mqtts://" IOT_CONFIG_IOTHUB_FQDN;
 static const char* device_id = IOT_CONFIG_DEVICE_ID;
-static const int mqtt_port = 8883;
+static const int mqtt_port = AZ_IOT_DEFAULT_MQTT_CONNECT_PORT;
 
 // Memory allocated for the sample's variables and structures.
 static esp_mqtt_client_handle_t mqtt_client;
diff --git a/examples/Azure_IoT_Hub_ESP8266/Azure_IoT_Hub_ESP8266.ino b/examples/Azure_IoT_Hub_ESP8266/Azure_IoT_Hub_ESP8266.ino
index 72ca043..6916850 100644
--- a/examples/Azure_IoT_Hub_ESP8266/Azure_IoT_Hub_ESP8266.ino
+++ b/examples/Azure_IoT_Hub_ESP8266/Azure_IoT_Hub_ESP8266.ino
@@ -6,7 +6,7 @@
  * It uses our Azure Embedded SDK for C to help interact with Azure IoT.
  * For reference, please visit https://github.com/azure/azure-sdk-for-c.
  * 
- * To connect and work with Azure IoT Hub you need a MQTT client, connecting, subscribing
+ * To connect and work with Azure IoT Hub you need an MQTT client, connecting, subscribing
  * and publishing to specific topics to use the messaging features of the hub.
  * Our azure-sdk-for-c is an MQTT client support library, helping to compose and parse the
  * MQTT topic names and messages exchanged with the Azure IoT Hub.
diff --git a/examples/Azure_IoT_Hub_RealtekAmebaD/Azure_IoT_Hub_RealtekAmebaD.ino b/examples/Azure_IoT_Hub_RealtekAmebaD/Azure_IoT_Hub_RealtekAmebaD.ino
index 71f1ecb..c7831b5 100644
--- a/examples/Azure_IoT_Hub_RealtekAmebaD/Azure_IoT_Hub_RealtekAmebaD.ino
+++ b/examples/Azure_IoT_Hub_RealtekAmebaD/Azure_IoT_Hub_RealtekAmebaD.ino
@@ -36,7 +36,7 @@
 static const char* ssid = IOT_CONFIG_WIFI_SSID;
 static const char* password = IOT_CONFIG_WIFI_PASSWORD;
 static const char* host = IOT_CONFIG_IOTHUB_FQDN;
-static const int mqtt_port = 8883;
+static const int mqtt_port = AZ_IOT_DEFAULT_MQTT_CONNECT_PORT;
 
 // Memory allocated for the sample's variables and structures.
 static WiFiUDP ntp_udp_client;