A free program for Android, by UnitedAppStudio.

Simple Control SoftKey – Home Back Button is an easy-to-use tool that allows you to create custom soft keys for your Android phone. These custom keys can be used to quickly navigate the home screen or any other screen of your device. With the app, you can set a custom key to launch your favorite app, or you can set a custom key to help you open the Settings menu.

Simple Control SoftKey – Home Back Button will also allow you to set a custom key to quickly navigate through your device’s recent menu. This option can be used to quickly open your recent apps.