I also use Waze on my iPhone 5 and the Real Time Traffic Information is amazing! It's navigation gets you around road construction delays and notifies you of Police, Speed Cameras, and accidents which is a blessing in the DC Metro Area. My wife even uses Waze in her X5M instead of the BMW Navigation system.
Instead of looking down at your phone screen, just pair the Bluetooth on your device and set the audible warnings and turn-by-turn directions. This way you can keep your phone charged via a USB charger in your arm console or a 12V charger in your cigarette lighter.
2012 550xi MSport - everything but TV's in the head rests!