Set the traffic lights up to broadcast a signal to the cell phones to flash the screen for a red light, don't walk sign etc.
Ultimately, I'd just call it cleaning the gene pool when your Angry Birds becomes more important than your life and limbs.
Safety course...
THE CORRECT SPEED FOR USING A PHONE IS ZERO MPH /KPH
Remember, it won't kill you to pull over to answer that call or text!