Kind of. An LCD display has one backlight which illuminates the entire screen with one brightness. So a black screen and a white screen will use the same amount of electricity if both screens are set to the same brightness, even though to us a white screen looks brighter. Using a dark theme won’t save any electricity, but it won’t use any more either.
Other display types use self illuminating pixels. Like OLEDs and plasma screens. So a screen which is mostly black uses a lot less electricity than a screen which is mostly any other color but black. Using a dark theme would use substantially less electricity.
Even a CRT would use less electricity if you switch to dark theme while still using one, because the cathode ray wouldn’t have to light up the black pixels.
My (possibly mistaken) understanding is that the vast majority of phones are AMOLED which does not have per pixel illumination. AMOLED is still considered superior because of physical thinness, efficiency, refresh rate, et cetera.
The battery thing is not true most of the time and the rest is subjective.
What’s to say either dark or light is better in all cases all of the time?
Depends on if the display is OLED, right?
Kind of. An LCD display has one backlight which illuminates the entire screen with one brightness. So a black screen and a white screen will use the same amount of electricity if both screens are set to the same brightness, even though to us a white screen looks brighter. Using a dark theme won’t save any electricity, but it won’t use any more either.
Other display types use self illuminating pixels. Like OLEDs and plasma screens. So a screen which is mostly black uses a lot less electricity than a screen which is mostly any other color but black. Using a dark theme would use substantially less electricity.
Even a CRT would use less electricity if you switch to dark theme while still using one, because the cathode ray wouldn’t have to light up the black pixels.
Makes a lot of sense, thanks
My (possibly mistaken) understanding is that the vast majority of phones are AMOLED which does not have per pixel illumination. AMOLED is still considered superior because of physical thinness, efficiency, refresh rate, et cetera.