[youtube http://www.youtube.com/watch?v=MzSJKpsNUFo&color1=0xb1b1b1&color2=0xcfcfcf&feature=player_embedded&fs=1]
It’s true! The built-in compass can be used as a metal detector, allowing you to detect keys that are very close to the phone. Is this particularly useful? Probably not, but now you can rub your phone against people like a stud finder and perhaps make new friends when you search for their “keys.”
Some folks at HDblog.it shot some video of the app in action. Worth a look.