Most people need to keep in touch on the move, whether it's a work phone call or just catching up with your family, holding, or even touching your phone while you're driving your car will cop you a hefty fine from the police in your state, plus a few points on your licence.
If you need to look at your phone for navigation, then you'll want to get yourself a car phone holder to place the phone somewhere where you can see if safely without having to look too far away from your view of the road. If you're using your phone for navigation, then it's going to start burning through your battery pretty fast, it's been a long time since any of us were using an Nokia 6210. In which case, a wireless car charger or wireless charging pad is going to come in use. No need to plug it in just put your phone in position and off you go.
If you're car is a little older and didn't come with bluetooth connection, or maybe even a usb connection, then playing your favourite tunes while you're stuck on the freeway getting to work is going to be difficult. There is a where a bluetooth fm transmitter can come in useful, connect your phone to it via bluetooth, tune your car radio in to the frequency set on the fm transmitter and you're set, no more Smooth FM for you.