Blinkers are really important.
Car blinkers tell you when the driver ahead of you is slowing down to turn. If you don't see a blinker, you might have a really bad accident. And if you don't use your own blinkers, the car behind you might ram you up the ass. So I say it's really important to use your own blinkers, and be aware of the blinkers of other motorists. A blinker on a phone means it's a really important phone.