The multi-output feature in Prime allows users to connect their iPad or iPhone device to an audio interface and mixer. This feature allows users to route their stems to specific channels for more mixing control.
Click here to learn more about Prime: http://loopcommunity.com/prime
Available for free in the App Store.
Mac: https://apps.apple.com/us/app/prime-multitrack-app/id1289813088?mt=12
iPad/iPhone: https://apps.apple.com/us/app/prime-multitrack-app/id664688175