This is the one point on which I agree with Oprah: the car is a no-cellphone zone. I don't talk to people who are obviously driving. I ask them to call back later.

Anyone who disagrees is part of the problem. The research is conclusive: multitasking is a myth. All you're doing is switching attention back and forth from one task to the other. It's dangerous, and using a phone in the car needs to have the same stigma as drinking and driving.
I'd totally be into cell phone jammers as a mandatory device if you're ticketed for distracted driving, just like interlock devices. Say six months or a year as a first offense (five years if you injure someone), and then grade it out exponentially from there. Second offense, five years, third offense ten years, etc.
And then add license suspensions along with it.

Of course, this would have to go along with the police deciding it was a priority again, which they're clearly not doing at the moment.
Unlike every other massive public health problem, all of us can actually make a difference with distracted driving:

1) Commit to not using your phone in any way while driving, and

2) Whenever there's an opportunity to do so in a minimally obnoxious way, try to convince others to do the same.
How about you fuckers on longboarders talking long distance to some long lost longing long dicker?? Huh? Huh?!

Fucking chancer it's a monkey outside for you fucking wankers. Slob a dobber will ya?