Smart Screen On/Off (All in one) is an Android application that enables you to lock and unlock your device without using the power button. This app is not a widget and can be convenient for those who want to avoid using the power button to turn off the device. You can easily turn off the screen by clicking on the app or shortcut icon, and it also supports a shaking detector that allows you to shake your phone to turn on/off the screen. The app uses Device Administration function in Android 2.2 or later, so you must activate it before using it.

The home screen will show two app icons after installation, one for locking the screen and the other for configuration. The app provides various features such as vibration and playing short sound when locking the screen, locking screen via shortcut in Notification bar, and backing to the home screen automatically after unlocking. You can also configure the settings according to your preferences. Additionally, the app supports the Device Administrator permission, which makes the device lock immediately. The app won't drain your battery, and you can uninstall it directly by pressing the Uninstall button in the Setting screen or by deactivating the device administration function.