Android Overdraw: Stop Painting Pixels Twice

Overdraw is wasted GPU work from painting the same pixel multiple times in a single frame, like painting a wall red then painting it white. This burns GPU cycles, causing UI stutter and draining battery. Find it using the 'Debug GPU overdraw' developer option and fix it by removing unnecessary backgrounds from covered views and flattening complex layouts. The main footgun is removing backgrounds that are actually required for visual states like touch ripples or for views that might be temporarily empty.