Creating a game for Android is easy with Construct 2. If you haven't already, download the Free edition and get going with the Beginner's guide!
You'll need to add touch controls. See this tutorial on touch controls for help on that.
Different devices have different size screens. See supporting multiple screen sizes.
Testing and publishing
If your phone browser is fast enough, you can try previewing over Wifi during development. (This requires a Construct 2 license.)
For best results publish with Crosswalk, which is like Google Chrome for Android turned in to a wrapper for native apps. For more information see How to export to Android with Crosswalk.
You'll need a Construct 2 license to publish. See the store for options.
How to make iPhone and iPad games
How to make an iOS web app
How to make a Windows 8 app
How to make a Windows Phone 8 app
How to export for Firefox Marketplace
Publishing and promoting your Construct 2 game
Happy app making!