Customizing the phone is a huge benefit that Android has over it’s other rivals. There are many launchers, themes and widgets available on the Google Play Store which will completely change the look and feel of any Android device. Especially if the Android device is rooted, then there are various hacks available for the smartphone.
XDA Recognized Developer rovo89 has created the Xposed Framework for the AT&T Samsung Galaxy S4 which will help in customizing the Galaxy S4 greatly. It is a great alternative to installing any theme based custom ROMs as it will give the device some added personality and features.