diff --git a/dom/datastore/DataStore.jsm b/dom/datastore/DataStore.jsm
index 777738528a35..874ea23553d1 100644
--- a/dom/datastore/DataStore.jsm
+++ b/dom/datastore/DataStore.jsm
@@ -19,6 +19,10 @@ const REVISION_UPDATED = "updated";
 const REVISION_REMOVED = "removed";
 const REVISION_VOID = "void";
 
+// This value has to be tuned a bit. Currently it's just a guess
+// and yet we don't know if it's too low or too high.
+const MAX_REQUESTS = 25;
+
 Cu.import("resource://gre/modules/DataStoreDB.jsm");
 Cu.import("resource://gre/modules/ObjectWrapper.jsm");
 Cu.import('resource://gre/modules/Services.jsm');
@@ -70,14 +74,42 @@ DataStore.prototype = {
     });
   },
 
-  getInternal: function(aWindow, aResolve, aStore, aId) {
-    debug("GetInternal " + aId);
+  getInternal: function(aStore, aIds, aCallback) {
+    debug("GetInternal: " + aIds.toSource());
 
-    let request = aStore.get(aId);
-    request.onsuccess = function(aEvent) {
+    // Creation of the results array.
+    let results = new Array(aIds.length);
+
+    // We're going to create this amount of requests.
+    let pendingIds = aIds.length;
+    let indexPos = 0;
+
+    function getInternalSuccess(aEvent, aPos) {
       debug("GetInternal success. Record: " + aEvent.target.result);
-      aResolve(ObjectWrapper.wrap(aEvent.target.result, aWindow));
-    };
+      results[aPos] = aEvent.target.result;
+      if (!--pendingIds) {
+        aCallback(results);
+        return;
+      }
+
+      if (indexPos < aIds.length) {
+        // Just MAX_REQUESTS requests at the same time.
+        let count = 0;
+        while (indexPos < aIds.length && ++count < MAX_REQUESTS) {
+          getInternalRequest();
+        }
+      }
+    }
+
+    function getInternalRequest() {
+      let currentPos = indexPos++;
+      let request = aStore.get(aIds[currentPos]);
+      request.onsuccess = function(aEvent) {
+        getInternalSuccess(aEvent, currentPos);
+      }
+    }
+
+    getInternalRequest();
   },
 
   updateInternal: function(aResolve, aStore, aRevisionStore, aId, aObj) {
@@ -161,6 +193,17 @@ DataStore.prototype = {
     };
   },
 
+  getLengthInternal: function(aResolve, aStore) {
+    debug("GetLengthInternal");
+
+    let request = aStore.count();
+    request.onsuccess = function(aEvent) {
+      debug("GetLengthInternal success: " + aEvent.target.result);
+      // No wrap here because the result is always a int.
+      aResolve(aEvent.target.result);
+    };
+  },
+
   addRevision: function(aRevisionStore, aId, aType, aSuccessCb) {
     let self = this;
     this.db.addRevision(aRevisionStore, aId, aType,
@@ -205,16 +248,6 @@ DataStore.prototype = {
     );
   },
 
-  throwInvalidArg: function(aWindow) {
-    return aWindow.Promise.reject(
-      new aWindow.DOMError("SyntaxError", "Non-numeric or invalid id"));
-  },
-
-  throwReadOnly: function(aWindow) {
-    return aWindow.Promise.reject(
-      new aWindow.DOMError("ReadOnlyError", "DataStore in readonly mode"));
-  },
-
   exposeObject: function(aWindow, aReadOnly) {
     let self = this;
     let object = {
@@ -235,15 +268,18 @@ DataStore.prototype = {
       },
 
       get: function DS_get(aId) {
-        aId = parseInt(aId);
-        if (isNaN(aId) || aId <= 0) {
-          return self.throwInvalidArg(aWindow);
+        aId = this.parseIds(aId);
+        if (aId === null) {
+          return this.throwInvalidArg(aWindow);
         }
 
         // Promise<Object>
         return self.newDBPromise(aWindow, "readonly",
           function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
-            self.getInternal(aWindow, aResolve, aStore, aId);
+            self.getInternal(aStore, Array.isArray(aId) ?  aId : [ aId ],
+                             function(aResults) {
+              aResolve(Array.isArray(aId) ? aResults : aResults[0]);
+            });
           }
         );
       },
@@ -251,11 +287,11 @@ DataStore.prototype = {
       update: function DS_update(aId, aObj) {
         aId = parseInt(aId);
         if (isNaN(aId) || aId <= 0) {
-          return self.throwInvalidArg(aWindow);
+          return this.throwInvalidArg(aWindow);
         }
 
         if (aReadOnly) {
-          return self.throwReadOnly(aWindow);
+          return this.throwReadOnly(aWindow);
         }
 
         // Promise<void>
@@ -268,7 +304,7 @@ DataStore.prototype = {
 
       add: function DS_add(aObj) {
         if (aReadOnly) {
-          return self.throwReadOnly(aWindow);
+          return this.throwReadOnly(aWindow);
         }
 
         // Promise<int>
@@ -282,11 +318,11 @@ DataStore.prototype = {
       remove: function DS_remove(aId) {
         aId = parseInt(aId);
         if (isNaN(aId) || aId <= 0) {
-          return self.throwInvalidArg(aWindow);
+          return this.throwInvalidArg(aWindow);
         }
 
         if (aReadOnly) {
-          return self.throwReadOnly(aWindow);
+          return this.throwReadOnly(aWindow);
         }
 
         // Promise<void>
@@ -299,7 +335,7 @@ DataStore.prototype = {
 
       clear: function DS_clear() {
         if (aReadOnly) {
-          return self.throwReadOnly(aWindow);
+          return this.throwReadOnly(aWindow);
         }
 
         // Promise<void>
@@ -410,6 +446,15 @@ DataStore.prototype = {
         });
       },
 
+      getLength: function DS_getLength() {
+        // Promise<int>
+        return self.newDBPromise(aWindow, "readonly",
+          function(aResolve, aReject, aTxn, aStore, aRevisionStore) {
+            self.getLengthInternal(aResolve, aStore);
+          }
+        );
+      },
+
       set onchange(aCallback) {
         debug("Set OnChange");
         this.onchangeCb = aCallback;
@@ -437,10 +482,6 @@ DataStore.prototype = {
         }
       },
 
-      /* TODO:
-         getAll(), getLength()
-       */
-
       __exposedProps__: {
         name: 'r',
         owner: 'r',
@@ -452,11 +493,43 @@ DataStore.prototype = {
         clear: 'r',
         revisionId: 'r',
         getChanges: 'r',
+        getLength: 'r',
         onchange: 'rw',
         addEventListener: 'r',
         removeEventListener: 'r'
       },
 
+      throwInvalidArg: function(aWindow) {
+        return aWindow.Promise.reject(
+          new aWindow.DOMError("SyntaxError", "Non-numeric or invalid id"));
+      },
+
+      throwReadOnly: function(aWindow) {
+        return aWindow.Promise.reject(
+          new aWindow.DOMError("ReadOnlyError", "DataStore in readonly mode"));
+      },
+
+      parseIds: function(aId) {
+        function parseId(aId) {
+          aId = parseInt(aId);
+          return (isNaN(aId) || aId <= 0) ? null : aId;
+        }
+
+        if (!Array.isArray(aId)) {
+          return parseId(aId);
+        }
+
+        for (let i = 0; i < aId.length; ++i) {
+          aId[i] = parseId(aId[i]);
+          if (aId[i] === null) {
+            return null;
+          }
+        }
+
+        return aId;
+      },
+
+
       receiveMessage: function(aMessage) {
         debug("receiveMessage");
 
diff --git a/dom/datastore/tests/Makefile.in b/dom/datastore/tests/Makefile.in
index 99b939895aa0..e77bd21fc3fe 100644
--- a/dom/datastore/tests/Makefile.in
+++ b/dom/datastore/tests/Makefile.in
@@ -26,6 +26,8 @@ MOCHITEST_FILES = \
   file_app.sjs \
   file_app.template.webapp \
   file_app2.template.webapp \
+  test_arrays.html \
+  file_arrays.html \
   $(NULL)
 
 include $(topsrcdir)/config/rules.mk
diff --git a/dom/datastore/tests/file_arrays.html b/dom/datastore/tests/file_arrays.html
new file mode 100644
index 000000000000..29be559be110
--- /dev/null
+++ b/dom/datastore/tests/file_arrays.html
@@ -0,0 +1,108 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for DataStore - add([array]) remove([array])</title>
+</head>
+<body>
+<div id="container"></div>
+  <script type="application/javascript;version=1.7">
+
+  var gStore;
+
+  function is(a, b, msg) {
+    alert((a === b ? 'OK' : 'KO') + ' ' + msg)
+  }
+
+  function ok(a, msg) {
+    alert((a ? 'OK' : 'KO')+ ' ' + msg)
+  }
+
+  function cbError() {
+    alert('KO error');
+  }
+
+  function finish() {
+    alert('DONE');
+  }
+
+  function testGetDataStores() {
+    navigator.getDataStores('foo').then(function(stores) {
+      is(stores.length, 1, "getDataStores('foo') returns 1 element");
+      is(stores[0].name, 'foo', 'The dataStore.name is foo');
+      is(stores[0].readOnly, false, 'The dataStore foo is not in readonly');
+
+      var store = stores[0];
+      ok("get" in store, "store.get exists");
+      ok("update" in store, "store.update exists");
+      ok("add" in store, "store.add exists");
+      ok("remove" in store, "store.remove exists");
+      ok("clear" in store, "store.clear exists");
+
+      gStore = stores[0];
+
+      runTest();
+    }, cbError);
+  }
+
+  function testStoreAdd() {
+    var objects = [];
+    for (var i = 0; i < 300; ++i) {
+      objects.push(i);
+    }
+
+    function testStoreAddInternal() {
+      if (!objects.length) {
+        ok(true, "We inserted 300 items");
+        runTest();
+        return;
+      }
+
+      var obj = objects.shift();
+      gStore.add(obj).then(function() {
+        ok(true, "We inserted a new item!");
+        testStoreAddInternal();
+      }, cbError);
+    }
+
+    testStoreAddInternal();
+  }
+
+  function testStoreGet() {
+    var objects = [];
+    for (var i = 1; i <= 300; ++i) {
+      objects.push(i);
+    }
+
+    gStore.get(objects).then(function(data) {
+       is(data.length, objects.length, "Get - Data matches");
+       for (var i = 0; i < data.length; ++i) {
+         is(data[i], objects[i] - 1, "Get - Data matches: " + i + " " + data[i] + " == " + objects[i]);
+       }
+       runTest();
+    }, cbError);
+  }
+
+  var tests = [
+    // Test for GetDataStore
+    testGetDataStores,
+
+    // Add many items
+    function() { testStoreAdd() },
+    function() { testStoreGet() },
+  ];
+
+  function runTest() {
+    if (!tests.length) {
+      finish();
+      return;
+    }
+
+    var test = tests.shift();
+    test();
+  }
+
+  runTest();
+  </script>
+</body>
+</html>
diff --git a/dom/datastore/tests/file_basic.html b/dom/datastore/tests/file_basic.html
index cf0c0e059775..cbeac57cd318 100644
--- a/dom/datastore/tests/file_basic.html
+++ b/dom/datastore/tests/file_basic.html
@@ -98,6 +98,12 @@
     }, cbError);
   }
 
+  function testStoreGetLength(number) {
+    return gStore.getLength().then(function(n) {
+      is(number, n, "store.getLength() returns the right number");
+    }, cbError);
+  }
+
   function testStoreRemove(id) {
     return gStore.remove(id).then(function() {
       ok(true, "store.remove() is called");
@@ -149,6 +155,9 @@
                    runTest(); }, cbError); },
     function() { testStoreGet(gId, "hello world 2"); },
 
+    // getLength
+    function() { testStoreGetLength(3).then(function() { runTest(); }, cbError); },
+
     // Broken remove
     function() { testStoreErrorRemove('hello world'); },
     function() { testStoreErrorRemove(true); },
diff --git a/dom/datastore/tests/test_arrays.html b/dom/datastore/tests/test_arrays.html
new file mode 100644
index 000000000000..35e3d187fcc9
--- /dev/null
+++ b/dom/datastore/tests/test_arrays.html
@@ -0,0 +1,121 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for DataStore - add([array]) remove([array])</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<div id="container"></div>
+  <script type="application/javascript;version=1.7">
+
+  var gHostedManifestURL = 'http://test/tests/dom/datastore/tests/file_app.sjs?testToken=file_arrays.html';
+  var gApp;
+
+  function cbError() {
+    ok(false, "Error callback invoked");
+    finish();
+  }
+
+  function installApp() {
+    var request = navigator.mozApps.install(gHostedManifestURL);
+    request.onerror = cbError;
+    request.onsuccess = function() {
+      gApp = request.result;
+      runTest();
+    }
+  }
+
+  function uninstallApp() {
+    // Uninstall the app.
+    var request = navigator.mozApps.mgmt.uninstall(gApp);
+    request.onerror = cbError;
+    request.onsuccess = function() {
+      // All done.
+      info("All done");
+      runTest();
+    }
+  }
+
+  function testApp() {
+    var ifr = document.createElement('iframe');
+    ifr.setAttribute('mozbrowser', 'true');
+    ifr.setAttribute('mozapp', gApp.manifestURL);
+    ifr.setAttribute('src', gApp.manifest.launch_path);
+    var domParent = document.getElementById('container');
+
+    // Set us up to listen for messages from the app.
+    var listener = function(e) {
+      var message = e.detail.message;
+      if (/^OK/.exec(message)) {
+        ok(true, "Message from app: " + message);
+      } else if (/KO/.exec(message)) {
+        ok(false, "Message from app: " + message);
+      } else if (/DONE/.exec(message)) {
+        ok(true, "Messaging from app complete");
+        ifr.removeEventListener('mozbrowsershowmodalprompt', listener);
+        domParent.removeChild(ifr);
+        runTest();
+      }
+    }
+
+    // This event is triggered when the app calls "alert".
+    ifr.addEventListener('mozbrowsershowmodalprompt', listener, false);
+    domParent.appendChild(ifr);
+  }
+
+  var tests = [
+    // Permissions
+    function() {
+      SpecialPowers.pushPermissions(
+        [{ "type": "browser", "allow": 1, "context": document },
+         { "type": "embed-apps", "allow": 1, "context": document },
+         { "type": "webapps-manage", "allow": 1, "context": document }], runTest);
+    },
+
+    // Preferences
+    function() {
+      SpecialPowers.pushPrefEnv({"set": [["dom.promise.enabled", true]]}, runTest);
+    },
+
+    function() {
+      SpecialPowers.setBoolPref("dom.mozBrowserFramesEnabled", true);
+      runTest();
+    },
+
+    // No confirmation needed when an app is installed
+    function() {
+      SpecialPowers.autoConfirmAppInstall(runTest);
+    },
+
+    // Installing the app
+    installApp,
+
+    // Run tests in app
+    testApp,
+
+    // Uninstall the app
+    uninstallApp
+  ];
+
+  function runTest() {
+    if (!tests.length) {
+      finish();
+      return;
+    }
+
+    var test = tests.shift();
+    test();
+  }
+
+  function finish() {
+    SimpleTest.finish();
+  }
+
+  SpecialPowers.Cu.import("resource://gre/modules/DataStoreChangeNotifier.jsm");
+  SimpleTest.waitForExplicitFinish();
+  runTest();
+  </script>
+</body>
+</html>