>how do you keep yourself from become a "phone zombie"?

I install only utility apps, a surf forecast app, a VPN token generator for work, and a few others.

I specifically don't install any social media apps on it.¹

I also use an older phone (iphone 5), and maybe that helps a bit too, since you have to be really motivated to browse the web on it.

1: I don't even have social media accounts, period, but that's another story.