screen-elder 

An elderly version of the screen-ager. An adult who spends an excessive amount of time on their personal electronic device, usually on social media, rudely ignoring the people around them, and oblivious to their immediate surroundings.

Husband to wife:
Honey, please get off instagram. We're at dinner with friends. That's rude. You're such a screen-elder

screen-elder by Casa de mil suenos August 13, 2017