My Xbox Live was a mobile app that launched for iOS in Dec. 2011 and for Android last month which allowed Xbox Live users to keep up with recent console activity, track achievements, and connect with friends. Today, iOS devices get the Companion feature update. 
 
The Companion feature allows users to physically control certain features of their Xbox directly from your phone. Users can launch games, browse and play Xbox Live videos or DVDs with play, pause, fast forward and rewind media controls, and navigate the console’s user interface.
 
The update is 27MB and is available through the App store. No official word yet on when these features will be available for Android devices.
 
source | apple insider