Only one of the three things you mentioned is comparable to F.lux: iOS Night Shift.<p>&gt; Kindle added &quot;Blue Shade&quot;<p>Blue Shade is, unfortunately, an exceedingly half-assed implementation; I wouldn&#x27;t be surprised if an intern wrote it over the course of a month or two. Unlike F.lux, (or Cf.Lumen on Android), it doesn&#x27;t change the color temperature of the screen—instead, it uses the same naive implementation as apps such as Twilight or Lux, which is a semitransparent reddish overlay that causes black colors to turn red. Considering that Kindles are running a completely customized Android ROM, Amazon could have done <i>so much better</i>.<p>&gt; Android announced &quot;Night Light&quot;<p>This is only for Google Play Books, and nothing else. [1]<p>[1] <a href="http:&#x2F;&#x2F;officialandroid.blogspot.com&#x2F;2015&#x2F;12&#x2F;silent-night-with-night-light.html" rel="nofollow">http:&#x2F;&#x2F;officialandroid.blogspot.com&#x2F;2015&#x2F;12&#x2F;silent-night-wit...</a>