It seems like I've had a car forever, and a phone forever, but the union of the two was always rocky. I'd always be trying not to rear end the guy in front of me, as I fumble with my phone in the cup holder.
For 20$ you can get a mount that lets you use your phone without taking your eyes of the road. I highly recommend the iOttie One Touch Dashboard Phone mount. If you drive, and don't already have one of these mounts, I strongly recommend taking one out for a spin.