Replay kit is a framework in iOS 9 which allows you to record screen and audio (including voice). All system events like notification and music from 3rd party apps(apple music, Spotify) are ignored from the video. The app does not have access to the video. Once you are finished a pop is displayed which allows users to share or save video to camera roll. There is also a broadcasting feature added in iOS 10 which allows users of your app to stream to other broadcast enabled apps that a users has on their device.