Wanam Xposed is an app to customize almost everything on your Samsung device, as long as it meets a few requirements. First of all, you need a Samsung Rom installed that's prior to the Lollipop version. Secondly, you need to install the Xposed module. If you don't do these two things, this app will be totally useless.
If you do meet these requirements, you'll find that Wanam Xposed allows you to customize practically every aspect of your Android, from the opacity of the status bar to the color of the keyboard.
Wanam Xposed can be really useful, but only if you're using a Samsung Rom and install Xposed first.