Definition

AVAudioSession is Apple’s audio management system used to control how an app interacts with the device’s audio hardware.

In CallKit apps, it is used to configure:

• microphone access
• speaker routing
• Bluetooth audio
• AirPods
• call audio behavior

Core Concept

CallKit manages:

• telephony lifecycle
• system call coordination

But your app is still responsible for:

configuring and handling actual audio behavior.

This is done using:

AVAudioSession

Why Audio Session Configuration Matters

Without proper audio configuration: