When that happens, you might see the "your phone is not registered on a network" on your screen, which means your SIM card can't connect to your wireless provider's network.

You can split screen on Android to enhance your productivity by multitasking using the built-in split screen mode or by using a third-party app.

Whether you use a Samsung tablet or multitask with the OnePlus Open's innovative software, we show how your Android phone opens apps in a split screen without your permission and how to stop it.