Screen Lock Button is a free Android app developed by Gopal Singh Sirvi, falling under the category of Utilities & Tools. As the name suggests, it provides a virtual screen lock button that allows you to quickly turn off the screen without having to press the physical button.

This app requires the "Device Administrator Permission" to function properly. It is easy to install and use, and it is especially useful for those who have a broken or malfunctioning screen lock button. However, users must keep in mind that in order to uninstall the app, they must first deactivate it from Privacy Settings > Device Administrators and then uncheck the application before uninstalling it.