Remember in the very early days of the apple app store they had shit like a virtual beer so if you held the phone up to your lips it looked like you were drinking a mug of beer? Pointless but kind of showed off the phone's capabilities? There would have been an app for put whatever color you want on the screen" with a set of RGB sliders. But nowadays that thing would require file access, phone, SMS, camera and payment permissions and would ruin your life for installing.