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I have Motion X, Mapquest, and TeleNav GPS. I like TeleNav the most followed by Motion X.
 
Navigon FTW. Europe, USA & Canada and Austraila.

iPad and iPhone.

Tom Tom was late and the app wasn't universal. Ever since Navigon came out I have used it. Excellent app.
 
I have used TomTom and CoPilot. While CoPilot was a good app and did the job, it was a little laggy at times. That is what got me to download TomTom. I really like TomTom and it is pretty quick to respond to input. Plus, with TomTom, I can get Homer Simpson to call out directions to me. :)
 
I've used both TT and Navigon (Western Europe) on my 3GS and rrefer Navigon every time.
 
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