Creating a game for Windows Phone 8 is easy with Construct 2. If you haven't already, download the Free edition and get going with the Beginner's guide!
Note: we strongly recommend exporting a Windows Store Universal app instead, which supports Windows Phone 8.1+. Support for Construct 2 games is significantly better in Windows Phone 8.1. For more information, see How to export Windows Store apps. The rest of this tutorial covers Windows Phone 8.0 only, which has some compatibility issues with Construct 2 games.
Setup
You need to download and install Visual Studio 2012 Express for Windows Phone 8 to be able to build apps for the Windows Phone store. It's a free download. Obviously having an actual Windows Phone 8 device is very useful for testing, so you may want to try and borrow or purchase one.
Development
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.
Note that despite the name, Construct 2's Windows 8 object does not currently work for Windows Phone 8. This is because Windows 8 and Windows Phone 8 are still currently two separate platforms, but they may be merged in future.
Exporting from Construct 2
First, ensure your project has the right Name, Description and Author properties set, since these will be used in the exported app. You'll also need to set a Fullscreen-in-browser mode, since mobile apps have to run fullscreen.
Then click Export project, and choose the Windows Phone 8 option. Continue with the next steps as you would for exporting an ordinary project.
In the export directory you will find a Visual Studio project. Note there are some icons and tiles in the Assets subfolder; you'll want to replace these with your own artwork with the same dimensions.
The main project file has the extension .sln (solution). Double-click it in Windows Explorer and Visual Studio should open it.
Testing from Visual Studio
If you've not used Visual Studio before, it's a complex and sophisticated tool for application development. However, you only need to use a small number of commands to test and build your app. To run the app and check how it works, click the run button in the toolbar, which should look something like this:
Visual Studio 2012 for Windows Phone 8 also includes a complete emulator for a Windows Phone 8. It may take a moment to start up, but once it's running it should start your app fairly quickly. This allows you to verify it is working OK on the Windows Phone 8 platform.
Building
Next to the run button on the toolbar should be a dropdown saying Debug. This is good for testing, but not for publishing. To release your app, click the dropdown and select Release. Then choose BUILD -> Build solution. When the build finishes, open the Bin\Release subfolder in Windows Explorer. This contains your .xap file, which is a compiled Windows Phone application.
Publishing
To submit an app to the Windows Phone store, visit this URL:
https://dev.windowsphone.com/en-us/AppSubmission/Hub
If you haven't published before, you'll need to sign up an account. This costs $99/year, but is also free if you're a DreamSpark student.
Once you're in the dashboard, click the Submit app button!
For more information such as setting up IAP and some other Windows Phone 8 specific tweaks, see Henry Hoffman's tutorial on Windows Phone games with Construct 2.
Other options
See also:
How to make a Windows 8 app
How to make Android games
How to make iPhone and iPad games
How to export to Firefox Marketplace