Modifying the Android devices is a very easy task. The device needs to be rooted after which the user can install custom ROMs. Another method to modify the Android device is the use of Xposed Framework. Using this, the user can achieve high level of customization on the Android without having to install the custom ROM.
One such modification is to change the background of certain apps. This can be done using the XBackground app within the Xposed Framework. This is available exclusively for the Samsung Galaxy Note 2.