I am working on an application that needs to save videos in local and should be able to play them only through the app. I am able to encrypt the video files and store them in app's folder. But my concern is how to decrypt and play the video files? I am able to see solutions for live streaming in web, but for decrypting and playing offline videos I am not able to find a proper way in IOS.
Apple's DRM technology, FairPlay Streaming (FPS) supports offline playback via persistent offline licenses.
You can find more info about apple FPS here: https://developer.apple.com/streaming/fps/