Ok, someone explain to me how black-and-white screen even makes a difference. The pixels are exactly the same, regardless of what color they're showing, it's not like it's switching to e-Ink.
It just seems like a placebo to make Samsung users think that they are saving battery because everything is grayscale. The only way I can see it actually working is if the black pixels actually turn off?
The S5 has a AMOLED screen. The black pixel do turn off. But they should have used gray instead of white. White draws a lot of power on AMOLED's imo