[throwaway823882]

1) Switch your bank account, 2) there are apps out there that replace the entire UI with a blank screen with 7 or 8 pre-selected apps (for Android anyway) and silence notifications. Helped me a ton, my phone doesn't grab my attention or show me anything unless I make it. I think the premium versions may allow you to completely block apps (like the App Store). Otherwise look into "Parental Controls" to lock down the phone to essentials.

If you feel you're about to start doing something on your phone that you don't want to, force yourself to get up and do 10 pushups, and then go accomplish some task that you have already set for yourself (chores, make a phone call, plan your day/week). If you can stick to it, the worst case is you'll be getting stuff done in addition to wasting time. Best case, you lose the interest in the scrolly thing because your attention gets focused on something else.