Texting and phone use in general. When I drive, about 80% of the drivers around me have their noses in their smart phones, as they wander into my lane or off nearly off the side of the road.
I watched an older woman take a left hand turn in front of oncoming traffic going about 45 mph. When she was hit and her airbag deployed, her phone smacked into face and left a visible mark.
they wander between lanes, cross the center divide, go 15 miles per hour below the speed limit, miss green light and fail to stop at red lights. And they kill people.