I was one to obsess over this and finally I struck jackpot this year with the 11 and got one looking like the left one.
After two months I tried turning true tone back on to see how long I could live with it and whether it is as bad as it was on first sight when I switch from my ‘perfect’ screen to a somewhat yellowish one. Turns out I got used to this and even prefer it now. Never looked back.
I noticed pictures having more pop to them and I even began to understand how people talk about the warmer temperature being the more accurate one among people working in professional fields regarding color accuracy. I don’t even notice the yellow or a dirty screen anymore.
Just my experience of course, but I felt I had been brainwashed by reading too much online about what is seen as the unicorn of great iphone screens and what is considered as ugly and unacceptable. Once I started this experiment I found out I clearly have a different preference.
I agree and ultimately this is nothing to lose sleep over. First world problems, really. I also have a preference for warmer light, blue is just too clinical and industrial. Can't relax, it feels like I'm at work.
Apple advertises the iPhone to have DCI-P3 gamut with a white point of approx 6300k. With the tint people are experiencing it looks to be nowhere near that. It's not slight variations as well since it can be observed by the naked eye. The blue one I received is 5800k at best. The tinted one probably around 5000k straight on and 4500k from an angle. There's several factors at play here I assume - panel variances, screen polarizer, and even from the way the glue cured. Even if you receive a perfectly white one it can still look yellow once you tilt it. I've experienced that with several Pixel 2 XL's.
There's actually a super easy way to measure the white point if anyone has a Colorimeter. Download DisplayCal and run the remote profiling feature. It'll host a website on the computer which then you enter the provided URL through Safari on the iPhone. The site will flash through a series of color patterns and tell you the brightness, white point, and the amount of red/green/blue. You can then dial in or reduce the amount of rgb until your desired white point. This is a fixable issue, but it's better to get one within the advertised specifications. If one likes a warmer panel it's better to work from a perfect panel and turn on true tone.
I'm sure there's a jailbreak for adjusting the rgb values but I'm completely new to jailbreaking so I don't know any for now. On Android you just download a custom kernel and reduce the numerical rgb values until it hits 6300k on DisplayCal. But that is getting really in depth as if you're going to do production work on the iPhone. If I was any younger I'd continue to play the panel lottery but for now I happy as long as I get a slightly colder panel.