I hope this works for my iTouch. This is the kind of thing I've always wanted. This, or music that changes based on your speed.
With more of these kinds of programs, imagine if videogamers seriously got in better shape? Aside from surviving the upcoming zombie apocalypse, the gamer demographic could get in a lot better overall shape... and maybe, just maybe, what if gamers ended up being the "attractive" demographic?
I know, that a pretty long shot, but still, you can dream.