Inter-App Audio (IAA) is a deprecated[1] technology developed by Apple Inc. which routes audio and MIDI signals between applications on the iOS mobile operating system. The technology was first introduced in 2013 in iOS 7 and deprecated in 2019 with the release of iOS 13.
Inter-App Audio is a host-plugin technology. An IAA host application connects to a node application to send and receive audio, MIDI, timeline information, and other signals.
Node applications can be of the following types:
At the moment, audio signal routing is only possible with a sampling rate of 44.1KHz.
Inter-App Audio was deprecated in 2019 with the release of iOS 13 in favor of the third version of Audio Units.[2]