This is keyboard to prepare for emergency situations. When finally configured, it can erase data (reset the phone settings) when you enter a special code. Reset code works only on the lock screen. It help if in the future someone tries to force you to enter a password. In that case, you enter the reset code instead password and press the Enter arrow.

You set your reset code in advance.

This is much more reliable than app's that use accessibility features to find the code, because accessibility