From Nicholas Pike:
Xbox Live is great - there's no questioning that, but sometimes you just really want to check your Buddy List without having
to turn on the Xbox, or fire up Xbox.com in a browser.
XBLFriends is your Xbox Buddy List(*) on your iPhone or iPod Touch.
See your select buddy list.
See what they are currently playing.
See their gamer pic.
See their gamer score, gamer reputation, and location.
See their list of recent games, including scores and last played dates.