Windows Phone 8 adds the ability for developers to sell additional features within the context of their
application, using 'In App Purchase.' Since Windows Phone 7 applications work on Windows Phone 8, we've also delivered the ability for you to add a few WP8 features to your WP7 app, which will run only when the application is run on a WP8 device. In this talk, Saral will walk us through exactly how you would add In-App Purchase to your WP7 game, so that it will appear when the app is used on WP8.
Download the code sample for this video here.