This application will let you change the Softkeys / Navigation Buttons fast and easily on your rooted Android device. This root app comes with more than 150+ different softkeys to choose from and the growing online database proivides even more user-submitted ones. If you got some navigation buttons you would like to see in this app just upload them to the gallery. Until I've added them, you can just use the import feature for these soft keys. This application needs root and "busybox" to be installed on non-nexus ROMs. This app will NOT overwrite your applied themes, or enable the navigation buttons on devices without them.
SoftkeyZ Root v14.5.6 apk link: https://www.dropbox.com/s/tjtg1duk3ev7756/SoftKeyZ%20Root%20v14.5.6.apk