I have a monochrome e-ink phone as my main portable device, I'm a huge fan of it. Completely cured me of Instagram and short-form video, it really does undo a lot of dopamine-seeking dark patterns. It's a cool aesthetic in itself too, a bit retrofuturistic.

Which one? Been tempted to try this

I've got the Bigme Hibreak Pro, I've de-googled mine but it's not a necessary thing to do if you don't want to.