Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.Download on the App Store
Audiobus is the app that makes the rest of your setup better.
High quality piano apps
What are the best sources of pianos on iOS?
I have AudioLayer, with imported pianos from Pianobook and Spitfire Labs (thanks Marcus Manderson). I have and love Ravenscroft. I have Korg Module Pro, and am choosing one (or both) of the pianos in that. I also use all the pianos I can find, in other synth apps.
But which are the other best sources of pianos (preferably editable), that I can also use in AUM or other DAWs on iPad?