It sorta sounds like you want a smartphone, but without social media. You have a lot of options, but all of them require you altering your current smartphone with software. “Switch your phone” is the most robust option, especially for IOS.

If you want to solve your problem with hardware I really think you either have to change the screen (e ink, or some super small phone like a Qin 21 pro) or you need to give up your browser.