just upgraded to android 6.0.1, rooted and tested to no avail. still waiting impatiently for android version.
aside from android, i used f.lux on CRT, LCD and two model of laptops. it works wonders on CRT and LED displays, unfortunately LCD (Samsung 740N 17" display) view is awful, nothing near eye comforting. view angle is affected, colors changed beyond recognition, etc. i think LCD technology is not that good to even consider tempering with but f.lux developers can focus on more common platforms like LED and AMOLED perhaps.
again great job guys and good luck to you.