I said &quot;obvious and trivial thing to do <i>once you know that blue light affects melatonin production.</i>&quot; In the past people did other hacks with CLUTs (like some early 3D games baking gamma correction into the CLUT so that proper linear lighting could be displayed without an expensive postprocessing pass). If you were aware of the blue light effect (I&#x27;m not a sleep scientist, I don&#x27;t know how long they&#x27;ve been aware of it) and had some low-level graphics programming knowledge, I don&#x27;t think it would require great leaps to come up with this solution. It&#x27;s just that no one else was interested in or aware of this problem.<p>Regardless of whether it was obvious or not, I hate the idea of extremely simple solutions being locked up behind patents, keeping the world today worse for the sake of hypothetical future innovations. It seems especially scummy the way they&#x27;re trumpeting over social media about the harm that blue light causes while quietly trying to profit over an extremely simple solution to it. More than likely they <i>know</i> that Apple will never allow this on their app store because of the potential for abuse the necessary APIs would provide, and their end game is hoping the angry mobs will convince Apple to implement this as an official feature (and thus, pay them royalties). And more than likely, Apple would have implemented this years ago, had f.lux been an open source student research program with no patent applications attached.