Like, have a switch that turns the white in to something more dark, so that we wouldn't be killing our eyes when browsing gag in the darkness. Kind of like youtube has or used to have a darken switch or something like that.
That's what the night shift is for on iphone, and flux for laptops is for. it lowers the amount of blue light emitted from computer screens which is what causes you to stay awake more at night. the blue light is also the wavelength that is "brighter" in the sense that it's the one that strains your eyes more.