The official
My Xbox Live app has just been updated to now also act as an Xbox Companion (I think the WP7 version has had this for a while?).
You can now use it to control the Dashboard, plus it has its own Quickplay menu to launch recent apps, and you can use it to control media.
I've just had a play, using it to browse the dashboard at first, then I used its own Quickplay menu to launch 4oD, and then used the app to control the video.
Very nice
EDIT:
The My Xbox Live app has also finally been released for Android. At the moment it is more like the initial iOS release, but hopefully will eventually get Companion features added.
https://play.google.com/store/apps/d....microsoft.xle