Acoustic Echo Cancellation (AEC) is supported via different methods. AEC is useful for speaker-phone configurations.

This module is an audio driver for iOS which is using the Hardware AEC block found in all iPhones. This has been tested with very high quality. (ref. VoiceProcessingIO)

The pulse module is an audio driver using the Linux Pulseaudio subsystem. The pulseaudio backend can be configured to enable AEC. Ref: https://github.com/alfredh/baresip/wiki/Using-PulseAudio:-module-echo-cancel

The module has a portable software AEC using the WebRTC SDK. The module is implementing the baresip aufilt API. It should work on different platforms such as Android, OSX and Linux.