Something I've noticed is the lack of social interaction, at least with those in the physical area. Teenagers rarely speak to anyone in the local vicinity, too attached to their phones and tablets to be bothered with talking. On a rare occasion the teenager might share a silly picture or video with someone at the table, but the bulk of the meal is spent in silence. This isn't as prevalent in adults, but I can see an increase in it, albeit much slower. Here's what I would do:
If I owned a restaurant, I'd enact a no phones policy. If you get a phone call, answer it, if you need to make a call, make the call. Want to take a picture of your food, or jot down a reminder for something later, go for it. However, you have a five minute time limit. After that, you better start talking to the people around you. If you're eating alone, do what you want. I'd rather you sit on facebook than talk to yourself.
The people you are sitting with are family, friends, REAL people. Those 500 facebook friends you've got on your list: take a good, long look at that list and count how many of them you actually hang out with. Chances are you spend zero time with them in the real world. I also don't count people from the past who somehow lurked into the present. If you live in Colorado and they live in Florida, what you ate for dinner hardly matters to them. It's about as useful as a tampon commercial to a guy.
So in short, put the phones down people, talk to the people who are actually PART of your real lives and not the ones lofting about in cyberspace. You can bs with your cyberfriends when you get home and go back to ignoring your family in front of the television. <3