Grey (via Marco Arment):
I hoped in vain, for a system-wide dark mode. Where the white background could go dark and the dark texts could go light.
But alas, now with the official release of iOS 8, there is no dark mode. I hoped Apple would implement it because dark mode isn't just a feature for night time use. For some of us dark mode is an accessibility feature.
Technology needs to adapt to its users. If you don't want to look at a bright, white app, then it should tone itself down – regardless of whether you have floaters or just want to read in bed.