I'm not really addicted to my phone. Most of the day I don't even know where it is. I am however a bit addicted to my laptop/desktop, but that's easier to avoid since it's location-dependent — I usually go on daily walks/jogs. Since there's also some external stimuli (people, weather, dogs, etc) it's much easier to keep the internet off my mind entirely.
If it's safe to do so, going on walks without the phone could be a good way to start a habit like this, IMO.