Here’s a video of someone using the iPHONE OCARINA APPLICATION. An ocarina is a small flute-like instrument, sort of a cross between a fancy kazoo and one of those recorders you played in kindergarten.
So some dude figured out a way to turn the iPhone into an ocarina. The touchscreen is a reasonable fascimile of the finger holes on the ocarina itself, but you make music by blowing into the iPhone’s microphone. Brilliant!