Function:   Turn off and lock the screen for your beloved phone.   Because this function already exists on your phone, it is the power button (power). But because pressing too much, it will quickly become greasy. So we write this application to help users reduce the burden on the power button (Power). This app uses the permissions - Device Administrator permission. To uninstall Lock Screen app: 1. Go to phone's settings > Security > Device administrators > Uncheck Screen Off and Lock.