Screen pinning

 Screen pinning is an app-pinning mechanism on Android devices that enables IT admins to lock an app to the screen and restrict other features and apps from being accessed. Android Screen Pinning is available for devices running on Android 5.0 Lollipop. Authorised users can unpin the device using a security PIN, pattern or password. Android Screen Pinning is commonly also referred to as Android Guided Access.

If the user no longer wants the device to run in the Screen Pinning mode, they can exit it by holding the Back and App Overview buttons simultaneously for a few seconds. If a password or PIN is set, the user will be prompted to enter it before the device exits the Screen Pinning mode.