I watch my teenagers and they have their phones attached to their hands practically all the time. I wouldn’t be surprised to see this adaptation as part of a teenagers evolution! As parents, we try to schedule time away from their phones and we encourage them to leave their phones downstairs over night as we do, but they like to text their friends in the evening and I get that. I remember talking to my friends too although I was sat on the stairs wrapped in my duvet as the phone was in the Hallway! It makes it tricky to police when phones are so accessible and they both want to use their phones as alarm clocks.