You might be interested in looking into an android phone with an eink screen - I find it to be a good deal less stimulating. I think a lot of people use the boox palma.
I have found vast improvements on my mood and focus by not bringing my phone with me to classes and work. Not checking it in the mornings (analog alarm clock!) or during the day has significantly improved my focus and how deep I go while working. And I just feel better. Not being bogged down by whatever is going on in the digital world while I am trying to churn as many good thoughts out of my brain is really quite freeing.