I developed Charlie's Video Player for my son Charlie. When he was very young, he loved watching videos on my iPad but he kept touching the screen and interupting the playback.
Charlie's Video Player let parents setup a playlist of videos (or audio files) and then it locks out the touch screen on playback. It was available for iOS and iPadOS, for free, in the App Store.
Update 03/07/25: Unfortunately, Charlie's Video Player is no longer available in the App Store. I'm hoping to return it there in the future (or open source the project on GitHub).