Saves battery by applying a filter thatturnsoff pixels of AMOLED screens.
AMOLED screens doesn’t have a backlight at all. Instead,eachlittle sub-pixel is like a tiny red, blue, or green coloredlight.If the screen is instructed to display black, it doesn’t needtoblock any light, it simply doesn’t light up any of thelittlecolored sub-pixels.
Black pixels save you a lot of power because those pixels canbeturned completely off. There is a relationship betweenbrightnessand power, but to really save juice you need a trueblack.