Nothing wrong with occasionally peeking at the phone. I'm talking about having the goddam thing all but surgically implanted in your face.
It could be the fact that damn near everyone below a certain age (and sometimes, those above that threshold) has their face glued to their smartphones. Interpersonal communication is fast becoming a dying skill here. :| No more mobiles suspended in the baby carriages, uh-uh, it's all about exposing the newborn to tablets now...gotta' start the little prince/princesses early yanno.

I've seen entire families finish a restaurant meal and proceed to drag out cellphones. Nobody talks anymore.
/rant
PS: And have I mentioned the times, more than once, when an entitled millennial literally runs into me on the sidewalk because they're too busy updating their FB status/texting/Tweeting/whatever, and have the nerve to accuse me of running into them?