The new Android specific features in XE7 include:
- Google Mobile Ads SDK (replacing AdMob for XE6 too)
- Immersive Fullscreen mode (for Android KitKat 4.4+)
- Splash screen support for Android
- Push notifications and advertising project options
- Project Manager support to add Java libraries to app
- Java2OP tool: Generate Object Pascal interfaces for Java Android Classes (separate download)
There are lots of other new features that are not specific to Android, but that will still help make your apps amazing for Android, iOS, Windows and OS X.