update readme files, add screenshot (#3)

* update readme files, add screenshot

* add screenshot to main readme

* use absolute URLs so the links work in the samples browser

README.md

@@ -12,7 +12,15 @@ urlFragment: all
 
 This repo contains Flutter samples that incorporate dual-screen enhancements for the Microsoft Surface Duo.
 
-Refer the to [dual-screen docs](https://docs.microsoft.com/dual-screen/) for more information and the [Surface Duo emulator download](https://docs.microsoft.com/dual-screen/android/get-duo-sdk).
+The [starter_sample](https://github.com/microsoft/surface-duo-sdk-samples-flutter/tree/master/starter_sample/) shows how to incorporate the Surface Duo SDK into Flutter so the device info is available in Dart. The [lightup_sample](https://github.com/microsoft/surface-duo-sdk-samples-flutter/tree/master/lightup_sample/) shows how to use the device info to create a layout that adapts to the dual-screen Surface Duo:
+
+![Flutter sample with a dual-screen layout](Screenshots/flutter-lightup-300.png)
+
+Refer the to [dual-screen docs](https://docs.microsoft.com/dual-screen/) for more information and the [Surface Duo emulator download](https://docs.microsoft.com/dual-screen/android/emulator/).
+
+## Adding dual-screen support to an existing app
+
+In addition to the samples in this repo, the [Adding Surface Duo support to the Flokk application blog post](https://devblogs.microsoft.com/surface-duo/adding-microsoft-surface-duo-support-to-the-flokk-application/) is a good reference for adding dual-screen support.
 
 ## Contributing
 

lightup_sample/README.md

@@ -1,16 +1,24 @@
-# duo_flutter_sample
+# Light-up Flutter app for Surface Duo
 
-A new Flutter project.
+This is the basic Flutter starter application modified to use the Surface Duo SDK and modify the layout for dual-screens.
 
-## Getting Started
+![Flutter sample app with layout adapted for two screens](../Screenshots/flutter-lightup-300.png)
 
-This project is a starting point for a Flutter application.
+## Get started
+
+This project is a starting point for a Flutter application that can be enhanced for the Surface Duo.
 
 A few resources to get you started if this is your first Flutter project:
 
 - [Lab: Write your first Flutter app](https://flutter.dev/docs/get-started/codelab)
 - [Cookbook: Useful Flutter samples](https://flutter.dev/docs/cookbook)
 
-For help getting started with Flutter, view our
-[online documentation](https://flutter.dev/docs), which offers tutorials,
+For help getting started with Flutter, view the [online documentation](https://flutter.dev/docs), which offers tutorials,
 samples, guidance on mobile development, and a full API reference.
+
+Visit the [Microsoft dual-screen documentation](http://docs.microsoft.com/dual-screen) for more information on the Surface Duo and the underlying Android helper libraries for dual-screen development.
+
+## Related links
+
+- [Lighting-up a Flutter application on Surface Duo blog post](https://devblogs.microsoft.com/surface-duo/lighting-up-a-flutter-application-on-microsoft-surface-duo/)
+- [Get the Surface Duo emulator](https://docs.microsoft.com/dual-screen/android/emulator/)

starter_sample/README.md

@@ -1,8 +1,10 @@
-# duo_flutter_sample
+# Basic Flutter sample with Surface Duo device info
 
-This is the basic starter application modified to use the Surface Duo SDK and surface the information in the Flutter application.
+A new Flutter project that includes the Surface Duo Android SDK and provides access to dual-screen device info from Dart.
 
-## Get Started
+The device info (`isDualScreenDevice` and `isAppSpanned`) is written to the console. For a more complete sample that _also_ updates the layout for two screens, refer to the [lightup_sample](../lightup_sample/).
+
+## Get started
 
 For details about this application check out the blog post on the [Surface Duo Developer Blog](https://devblogs.microsoft.com/surface-duo/get-started-with-flutter-on-surface-duo/)
 
@@ -11,8 +13,12 @@ A few resources to get you started if this is your first Flutter project:
 - [Lab: Write your first Flutter app](https://flutter.dev/docs/get-started/codelab)
 - [Cookbook: Useful Flutter samples](https://flutter.dev/docs/cookbook)
 
-For help getting started with Flutter, view the Flutter
-[online documentation](https://flutter.dev/docs), which offers tutorials,
+For help getting started with Flutter, view the [online documentation](https://flutter.dev/docs), which offers tutorials,
 samples, guidance on mobile development, and a full API reference.
 
 Visit the [Microsoft dual-screen documentation](http://docs.microsoft.com/dual-screen) for more information on the Surface Duo and the underlying Android helper libraries for dual-screen development.
+
+## Related links
+
+- [Get started with Flutter on Surface Duo blog post](https://devblogs.microsoft.com/surface-duo/get-started-with-flutter-on-surface-duo/)
+- [Get the Surface Duo emulator](https://docs.microsoft.com/dual-screen/android/emulator/)