Hi, I have an old iPhone 4S that I have been using as a Touch. It doesn't have a service plan/data plan on it. I have heard that apps such as Navigon, TomTom, Garmin, CoPilot, and Sygnic have offline navigation through their downloaded maps. I understand that this works through the iPhone GPS signal. I was wondering if anyone has tried these "offline" before. If so, how accurate are they? Does voice navigation still work offline? How well does it autocorrect on a route offline? Thanks for the help.