When Knox Chandler was profiled in Guitar Moderne, he was already incorporating an iPad into a rig that included a laptop. More recently he has gone all iOS and was kind enough to tell Guitar Moderne about it.
Sampling pioneer J.A. Deane gives an overview and an update on the state of live sampling, with lots of invaluable info if you are considering (as I am) investigating an iPad based system. Oh, how far we have come.