App Sitter is a screen time app for families. Technically, it's based on a Mobile Device Management (MDM) system that communicates directly with the mobile device and sends it management instructions.

Parents can enroll their children's mobile devices into the service and then use the app to "lock" the children's devices manually or set a time based schedule for when the device should be locked. For instance the parents can schedule that their children's devices should be locked during the night.