App pinning is a feature available on Android devices that allows users to "lock" an apps screen to a single app, making other apps on the device inaccessible. When enabled, a pinned app takes over the entire home screen display, and while its pinned, you cant access other apps. This feature can be useful in situations where you want to prevent accidental dismissal of an app, or when you want to hand your phone to someone else and restrict their access to only one app.

To enable app pinning on an Android device, follow these steps:

1. Open your phones Settings app.
2. Tap Security or Security & location > Advanced > App pinning.
3. Turn on App pinning.

Once app pinning is enabled, you can pin an apps screen by following these steps:

1. Go to the screen you want to pin.
2. Swipe up to the middle of your screen and hold.
3. At the top of the image, tap the apps icon.
4. Tap Pin.

To unpin a screen, you need to enter your PIN, pattern, or password. To exit the pinned app, hold the "back" and “recent apps" navigation buttons down.

App pinning is available free of cost, allowing organizations to manually pin the required app and provision them as single-purpose devices, without any additional cost.