Forest app & Sleep Town app
The Forest app has a very simple premise: it helps you to stop using your phone (or tablet, or particular websites on your desktop) for a particular period of time. How? While the Forest app is running, it’s growing a tree. If you exit the Forest app while the tree is growing, it’ll die, and you’ll end up with a withered tree in your forest. It’s a pretty amazing way to give yourself a break from your device addictions and a good reason to put your phone down for a bit. If you pay for it, you can also narrow it down so that you are still allowed to visit a few select apps while you’re growing a tree (good for multi factor authentication while at work). If you think you will still cheat (or never remember to start growing a tree in the first place), then I would recommend the Freedom app instead.
Sleep Town app
From the same people as the Forest app, the Sleep Town app has a similar concept. You must hit a button on the app before your bed time to start building a house, and hit the button again before your ‘getting up time’ so that the building doesn’t collapse. Over time, you unlock other buildings and build up a whole city. It works just slightly less smoothly than its Forest counterpart, but is still quite motivating, and anything that helps make going to bed on time (or at least stop using your devices at a certain time) attractive for a while seems worth it to me. Again, if this doesn’t appeal, the Freedom app is a beefier alternative.