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.
AudioStretch Lite cool trick
This app, https://apps.apple.com/gb/app/audiostretch/id571863178 is an IAA generator which loads up fine in AUM, and is designed chiefly for people wanting to slow down tracks to learn them, but I just realised the free version also allows you to scrub manually back and forth through the sample, for some cool granular/delay type effects which you can then, obviously, record live into the file player. The paid for version allows a much greater range of time and pitch stretch. I’ll hang on a while to see if it hits the sales, but even the free version is a lot of fun for sample manipulation. - a poor person’s Samplr?