Audiobus Remote
"Audiobus Remote is a companion app for Audiobus which can either run on the same device or on a separate iPhone or iPad connected by Bluetooth. On newer devices running iOS 9 or later, Audiobus Remote also supports Split View and Slide Over mode.
Audiobus Remote transports your Audiobus-compatible music apps' controls onto a second screen. Some of the things you can do with Audiobus Remote:
Switching between apps Record or toggle individual loops in Loopy HD" --from the App Store description.
App type: App
App store link: 
Audiobus Remote
Developer: Audiobus Pty Ltd
Developer AB Forum Handle: @Michael
Additional Info
Discover apps with Remote Triggers in the compatible apps directory
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