You can get most of the way there just by turning off all notifications. I'm not an iOS guy, but on Android, there's something called 'do not disturb' - and it can be scheduled. AFAICT it's intended to let you shut your yammering phone off while you're asleep - I leave it on 23 hours a day. The only notification that makes a noise I've left 'on' is warnings of 'extreme weather events'. No LED blinking except for missed calls or texts from people in my address book. I never got sucked into social media, so can't speak to whether this approach might help there...