Lemur
The musical event of the year. Total control of Midi and Osc devices. I know people who bought the iPad just for this app.
SampleWiz
Excellent sampler for sound designers, but performance-oriented. Lot of features. Developed by Jordan Rudess of Dream Theater.
Download
touchAble
The best app to control Ableton Live. If you hack around with Ableton, live or in studio, is a must have app.
KORG iKaossilator
Another Korg masterpiece. A Dynamic Synthesizer to make tracks like a pro using just your fingertips. In v.2 you can export your performances audio or upload on Soundcloud.
