This experience is always eye opening. It always makes me wonder what the hell I was doing with that smart phone all the time. I just got it back (!after 7 weeks!) and I do 3 days on a battery because I hardly check it. I lost the habbit. I feel much better, when I bike to work I don't have a podcast playing (Twit, No Agenda, yes I miss it, I even burned two No Agendas to a CD for a long car ride, had to dig around the attic for burnable cds :)), I'm not whatsapping during work, not reading long posts on he toilet. I have time to think. Think about what to do, what to learn, how the day will look like. This alleviates a lot of stress, just having a clear and relaxed picture of what your day will look like.
In short: Just stop it. Just Stop overloading your brain. You know exactly what is wrong but you are too weak. Stare out the window, go on walks without your cell phone, quit facebook. The world will not miss you.
I have a very strong feeling that when we stopped being bored, stopped waiting, stopped doing nothing, stopped staring and replaced it with constant consuming of information, we lost something valuable. And indeed, those apps are shortcuts to dopamine release, it is hard to stop. I admit, getting my phone back was like getting a new gadget, but I try to restrain myself from using it. One small trick is to do most thing in the browser, it does not put notifications in your notification area.
By the way, you posted your question here to find an easy way out, to get a tip like: Scratch your left nut for 3 minutes once a day and feel better. But there is no such advice. There is no shortcut. You are going to have to do something radical if you really want change. If you really want change, delete all those accounts, get a dumb phone.
As a single footstep will not make a path on the earth, so a single thought will not make a pathway in the mind. To make a deep physical path, we walk again and again. To make a deep mental path, we must think over and over the kind of thoughts we wish to dominate our lives. -Henry David Thoreau
It is hard work.