This is a tool to lock the screen of your smartphone after a phone call. It fixes the weird behavior of almost all versions of Android, when after a phone call the screen stays unlocked even if it was locked before placing the call. That can be annoying when using bluetooth hands free and the phone stays in your pocket.The application appears in the list of running applications, but no worries - it does not consume any system resources, so you do not have to worry about your battery life. It needs to run in background to work properly. This app uses the Device Administrator permission. Without this permission it would not be possible to lock the screen through this app.If you experience any problems with this application, It would be great if you could describe it to me in an email rather than give a bad rating and uninstall. Mostly the problem can be solved with the right configuration or a compatibility fix.