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.
An Isolation Loop
Hainbach is doing a free/pay what you want soundpack on his Bandcamp:
as a gesture toward doing something creative with the current world shut-in time. People are posting the results to his reddit. This is what I came up with using my IPad, two samples from the pack, and a whole pile of apps, including the similarly coronafreebie Model D. If nothing else, it’s a bonanza time for free music stuff.