Using CallKit: How to Integrate Voice and Video Calling Into iOS Apps

This tutorial provides a comprehensive guide on integrating Apple's CallKit framework into iOS applications, allowing developers to enhance their VoIP apps with native iOS calling features. CallKit offers out-of-the-box UI components, eliminating the need for custom UI development, and ensures a consistent user experience by utilizing standard iOS interface elements like accept, cancel, and mute buttons during calls. It facilitates call management and notifications, even when the app is not actively running, by displaying incoming calls on the lock screen and supporting active call controls. The tutorial includes creating a sample app, StreamCall, which demonstrates receiving and making calls using primary CallKit classes such as CXProvider and CXCallController. It also covers customization options like setting custom ringtones and using PushKit for handling notifications while the app is closed, emphasizing the seamless integration of third-party VoIP apps with the native iOS calling experience.