Electronics
This seems entirely obvious, but how many times do we look at our phones because it vibrates and it's just the current weather or some step counter or whatever.
A few months ago, I spent a day disabling every one of these types of things. Now my phone only vibrates for something important and I don't get distracted constantly looking at it and then jumping onto various apps.
Or just go into into you app notifications list (on Android anyway), and deselect everything you don't want to see.