Finally it does work on iPhone 5. – NAVIGON U.S. Central Review

I reviewed earlier that it didn't work on iPhone 5, but it does. It just takes a loooooong time to extract a map. It said it was done downloading but no map. About 20 minutes later I was in another app and navigon pops up saying extracting map, so you may have to wait a bit but it will work.
Review by Mid Missouri on NAVIGON U.S. Central.