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.
Circuit Drone Ambient sort of trick/workflow (works on iOS too :))
I found this video yesterday and found it pretty useful for circuit owners, but the concept can easily be transferred to iOSical stuff too. I tried already successful with StepPolyArp in AUM. Maybe I can record later the jam and up it on soundcloud.
Hope you find it useful too, its pretty easy but I never thought of it before (basically its about setting the step length to 1)...