One thing I believe to be true: If you have a device near you, there is no amount of habit or self control you can enact to change the habits of using that device. The same with the type of device. If a device has internet capabilities, no amount of self control or habit forming will make you only use the reading app on that device. You will always lose the habit at some point.

A requirement for changing habits is changing the physical world. Picking a device with no internet browsing capabilities, like an e-reader or a physical book. Or going for a walk where you physically don't have your phone. Even putting a phone in the next room isn't enough, you have to be somewhere where you physically can't access the phone.

Humans are not capable of fixing attention habits in which the physical world is set up to make it feasible to lose your attention.