Turn by Turn Navigation is a full featured Windows Phone 7 navigation
app, wich has a recently released offline version.
Main features:
Voice-guided turn by turn Navigation with premium audio quality in 14 different language
Automatic map rotation according to your heading,
Automatic re-routing if you miss a turn.
The offline USA+CANADA version is now availablie with 50% off on the market!
Check it out:
http://www.windowsphone.com/s?appid=...0-cbe966cdd427