[shanebellone]

The Google Pixel has a number of settings for this. It has the standard slider, extra dim, night, and grayscale modes.

I always laugh when I see competition over brightness. I cannot wait for e-ink monitors to improve and wish someone would make an e-ink phone.

Edit: Those settings might be standard on Android and not actually Pixel specific.

[washadjeffmad]

I keep Extra Dim on at all times to lower the peak nits and to further dim the screen when using Night Light to read after dark.

The biggest saviors to my longtime night reading habits, though, have been OLED and how many websites and ebook apps have competent true black dark modes.

[aembleton]

Dark Reader addon is good for this and works on Firefox for Android https://addons.mozilla.org/en-US/firefox/addon/darkreader/