AVFoundation is a multimedia framework with APIs in Objective-C and Swift, which provides high-level services for working with time-based audiovisual media on Apple Darwin-based operating systems: iOS, macOS, tvOS, and watchOS. It was first introduced in iOS 4Exploring AV Foundation - WWDC 2011Framework AVFoundation - API Reference developer.apple.com and has seen significant changes in iOS 5 and iOS 6. Starting with Mac OS X Lion, it is now the default media framework for the macOS platform.
AVKit As a component of AVFoundation, AVKit is an API that comes with OS X Mavericks 10.9+ and can be used with Xcode 5.0+ for developing media player software for Mac.
The AVKit software framework is replacing QTKit which was deprecated in OS X Mavericks, and was discontinued with the release of macOS Catalina.
See also QuickTime Media Foundation
References
External links
Moving to AV Kit and AV Foundation presentation (video and slides) from WWDC 2013 at Apple Developer Moving to AV Kit and AV Foundation slides at Huihoo Foundation Documents Technical Note TN2300: Transitioning QTKit Code to AV Foundation at Apple Developer Archive