2Name: TomTom U.S.A.
This app provides navigation from Point A to B with 2D and 3D driving views, route calculations, spoken instructions, and estimated travel times. Those using an iPhone or iPod Touch will need a TomTom car kit with GPS receiver; the iPhone 3G and iPhone 3G S, which feature GPS, do not need the kit in order to function properly. Also features editions for other countries.
3Name: CoPilot Live North America
Also available in editions for other countries (including Australia and the U.K.), this app marries U.S. and Canada street maps with your iPhones GPS to guide users. Features include 2D and 3D driving views, a detour button for alternate routes, text-to-speech for directions, and a route optimizer for multistop trips.
4Name: MotionX GPS Drive
5Name: Magellan RoadMate 2010 North America
6Name: Google Earth
9Name: Mobile Maps US
10Name: MobileNavigator North America
11Name: MapQuest Navigator
Unlike many of these other apps, this one relies on a subscription service after the first 30-day trial period (it costs $3.99 per month, $9.99 for 90 days or $29.99 per year). This app includes turn-by-turn navigation, the ability to search through more than 16 million points of interest, traffic-based routing, routing to existing iPhone Address Book Contacts, and the ability to resume navigation after phone calls.