The full implementation of MIDI finally with iPad OS 4.2 (release version due out in only a few days) will substantially increase the potential of music sequencing programs on the iPad. There are currently some good iPad/iPhone multi-track sequencer apps like ( MultiTrack DAW , and Four Track , but they're restricted to 'audio' track recording only. With 4.2 OS midi implementaion, it should be only a short time (if that) before these apps will be adding the ability to rec midi tracks as well, and perhaps including GM/GS/XG midi sound fonts. It's really exiting to potentially have the recording features of Cakewalk Sonar and Cubase on an iPad soon.