InkEffect Is a simple app that enables you to quickly add a burst of your favorite colors to your Galaxy S3. You will need to be rooted and have a custom recovery installed as you will be flashing the mod in recovery. Once installed simply open the ink color changer and choose the desired color to complete the effect. This application has been pretty popular over at XDA over the past month. Grab it from the description link below!
Does it only affect the wallpaper? Neither this post nor the XDA post really explain what ink effect does other than that screenshot, so I'm assuming that's it?