Maybe I misunderstood what you were looking for... o.O
much more polished than Android in some areas, and if you want to do music writing on your phone, iOS is the clear winner. I have some stuff on my Note but I almost never use them. Caustic 2, RD3 HD, and Sunvox. There's no Nanostudio, though
As far as audiophiley stuff, there's FLAC Player on iOS that lets you play .flac files.
If Apple made an iPhone the size of the Galaxy Note, with a wacom digitizer/pen, I'd be all over it to be honest.