Superuser (for Android 4) is a control tool for Android superuser privileges. In contrast to other similar apps, this one is open-source. In just a few words, it's one of those apps that's great to have when you're using a rooted device.

With Superuser (for Android 4) you can do everything you'd expect from an app of its type: give and take privileges from any app that's installed on your Android, all from a simple and accessible interface.

You do need a rooted device in order to use Superuser (for Android 4). There's no point in trying to install it if you haven't rooted your device beforehand, it won't work.