Recently took trips to Central Michigan and North Carolina coast and Navigon was no use to us on our iPhone and 3G iPad. I'd assume any GPS on the iPhone or iPad would have failed as we had only Edge service in both locations. Good thing I had a Garmin!
Has anyone here had experiences with Navigon et al in Europe? And does it work for pedestrians? I'll be doing a few tours through Europe when we move back there, and an iPad seems like a pretty good idea - not for constant guided use (would look silly missing out on the sights because I'm too engrossed in the iPad), but as an efficient replacement for those crappy paper maps that you get from a Tourist Info booth.
I'm interested to know why Navigon failed for you (and why would you assume GPS would fail because of an Edge connection)?
The original reviews I saw on the European versions were positive. Theoretically you should have better results in Europe since that's where Navigon's corporate offices are and where they have the largest installed base of hardware GPS receivers.