Texting while walking isn't funny anymore

Manny Fiori’s job is to make sure your phone doesn’t kill you. He guards the entrance to a garage near my San Francisco office and stops cars from hitting pedestrians so engrossed in screens they don’t notice they’re stepping into traffic. “People are so preoccupied nowadays,” says Mr. Fiori, a building worker who barks orders and even binds out his arms to stop both cars and people.