I have always been able to use HTC phones (with Super LCD3) display without a problem. I have owned HTC One (m7), HTC One Max, I skipped M8, now I am using M9+ Supreme Camera Edition. All these phones uses Super LCD3, and I look at the screen for hours e.g. watching you tube without any problem whatsoever. Note that my M9+ is still on Android 5 (Lollipop). I dare not upgrade to Android 6 because I read users get eye strain after upgrading.
I have purchases many other phones, LG V10, Huawei Mate 7, Samsung Note 5, even other HTC model like E9+ that uses IPS display all give me eye strain. So far, only HTC phones with Super LCD3 display I can use without a problem.
So now is time to upgrade my phone again. HTC has new model, HTC 10 and U Ultra that uses Super LCD5. The 10 is last year's model, so I bought the U Ultra (also because I prefer bigger screen), which comes with Android 7. Lo and behold, I get eye strain. My one hope and phone brand that I can use now is unusable. This sucks.
This eye strain is different than, say a PWM induced eye strain. PWM i feel the strain more inside my eye balls. This eye strain from the phone is more like a throbbing inside my head (skull, brain), from ears up.
This phone has no PWM. I am assuming that Super LCD5 is not causing eye strain to me (because Super LCD3 does not give me eye strain, but I cant know for sure), and I assume the cause of eye strain is really because of Android 7. I tried tinkering with color and display setting. Not much can be changed.
I have discovered that this combination that makes the eye strain a little bit better:
Disable HW overlay + use "CF.lumen" app and change the master color profile (change RGB values, and use the auto-brightness of the app instead of the phone's). These 2 combination helps to reduce the eye strain, but the eye strain is still there and not 100% gone.
The CF.lumen app says that if the phone is rooted, it can work better. How better I am not sure, but I am hoping the app can change things at root or kernel level to change the color is displayed. But rooting my new HTC U Ultra will void my warranty, and if it doesnt work, I would loose a lot in resale value if I need to sell the phone.
If anyone has a rooted phone, can you install and try the CF.lumen app, let the app control the phone's auto-brightness, and set any value RGB and brightness so that the app will control the color and brightness, and see if it helps to reduce eye strain or not.