You know I have mixed feelings about making music on iPads. Same goes for most of these “iPad Band” videos – they’re kitschy, usually don’t sound very good, and if it weren’t for the iPad/Pod/Phone part the actual sounds that are coming out wouldn’t be given a second thought by any human with working ears.
But this guy made one that sounds pretty good:
[youtube:http://www.youtube.com/watch?v=5kFoMvLTXc0&feature=related%5D
Looks like a mix of a couple good apps: GarageBand, Fingerjam, and some other thing that apparently has a glockenspiel interface? Good find!
WILL KUHN 
Percussive is the other one.
Thanks!