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.
I have been in a few apps that have audiobus in different locations around the screen. Sometimes the panel is on the bottom, sometimes it's on the right, etc etc. Sometimes it's in the way unless I hide it. It might be nice if we could move the orientation ourselves. Not a requirement and maybe others will chime in and tell me why this is a bad idea. Had the thought, though, and figured why not share it.