Just been looking at SatNavs for a US trip and came across this deal. I know there are better, but at £2.99 it's got to be worth a shot!
Some info from the site:
INTRODUCTORY OFFER: Get premium turn-by-turn GPS navigation on your iPhone with FREE MAP UPDATES for the unbelievable price of $4.99!
FREE MAP UPDATES THROUGH DECEMBER 2010
With free monthly map improvement updates downloaded directly to your iPhone and a complete new updated map every quarter, you can rest assured you have the most current and reliable maps guiding your way. And it doesnt stop there! If you see a street or address that needs updating, you can report it to the ALK® MapSure service. Were committed to verifying and adding your map update requests within 45 days. Guaranteed.
OFFLINE NAVIGATION - NO NEED TO RELY ON YOUR MOBILE NETWORK OR PAY ROAMING CHARGES
CoPilot Live stores the complete, detailed street-level map of USA directly on your iPhone so you can use your premium navigation offline without having to rely on your mobile network. No matter where you are, CoPilot Live is available to guide you with turn-by-turn directions along your route.
PACKED WITH POWERFUL NAVIGATION AND SAFETY FEATURES:
- Turn-by-turn voice-guided directions
- Clear 3D and 2D driving views with speed-variable zoom and full street names
- Lane Assist display and CoPilot ClearTurn for a realistic, clear display at complex intersections
- User interface designed to guide you clearly without unnecessary distraction
- Driver safety view that displays at-a-glance instructions and a large arrow of the upcoming turn
- Automatic day-night mode switching to reduce screen glare
- Customized routing for alternative modes of travel: Walking, Cycling, RV and Motorcycle
- Navigation to a house number, street, favorite place, intersection or address book contact
- Multiple-stop trips, waypoints, route optimization options and pre-trip planning features
- Millions of pre-loaded Points-of-Interest (POIs) to navigate to or call directly
- Smart call handling remembers your destination after a phone call
- Dial a POI (Point-of-Interest) by tapping on-screen
- Portrait/landscape display auto-switching and pinch-zoom
- Access iPod music controls from in-app