Touch Lock

Touch Lock is an app that lets you lock all the physical buttons and gesture commands on your Android device. This makes it so you can leave the device with a child to watch movies and YouTube videos without having to worry about anything, like them making random phone calls, switching the screen off, opening other apps, nothing. In short, it's a highly useful app for parents that might even prove useful for other adults who just want to watch movies with no distractions of any kind.