At least on my phone (LG G5), the lowest brightness setting is still incredibly bright in an otherwise dark room. I use Twilight[0] to dim it further, though unfortunately Google changed Android so it can't affect the soft buttons. (Which is fine for almost all apps because the soft button bar is black, but of course Chrome changes it to white with no way to fix it.)

[0] https://twilight.urbandroid.org

I recommend, instead of Twilight, to use Lux[0]. It has many settings and lets you completely set your own brightness curve, with "negative" brightnesses that darken your screen with an overlay included. Also lets you adjust color temp, of course. The free version had all the features I needed.

[0] https://play.google.com/store/apps/details?id=com.vitocassis...

Thanks for prompting me to go back and check the settings on the Darker(https://play.google.com/store/apps/details?id=com.mlhg.scree...) looks like it now dims the soft navigation buttons

iOS is the same. Even on the warmest setting and lowest brightness it's still very bright. Unfortunately, there is no app to do anything about it like there is on Android.

There is a setting, so I can tap three times with three fingers each time top open a menu and set a filter, and I choose low light mode

It's not the easiest mode to find, but works.

You can configure iOS Home button triple-click to invert the screen, so it's white text on a black background. There is a "Smart Invert" option so that photos are not affected.

You can also apply an accessibility filter to increase the darkness in iOS. I have this mapped to a triple home-button click and use it all the time (after reading to kids etc)

https://www.techrepublic.com/article/pro-tip-dim-your-ios-sc...

I'm on X so no more Home button, but good suggestion. For last 9 months I had my phone on grayscale, which was nice, but still a bit high for my taste.

You can go further by reducing white point in accessibility settings. The colour filters there also go beyond night shift.

Interesting. I was on grayscale for last couple of months, but didn't know I can reduce the white point also. Will try.

My TV, a Toshiba Regza, has dynamic brightness. It works very well as my primary monitor.