Based on my admittedly not that extensive experience, i.e. a one-month trip driving several hours a day every day in France, I have to admit that this is an activity where I felt the iPad was lacking. I would opt for a "true" GPS device over any navigational app on the iPad. Relying on 3G when traveling? What happened with us is we would often lose signal and often (of course) at really inconvenient times. Plus using 3G to navigate eats up the battery (can be remedied with a car charger) and your communication credits (cannot). YMMV.
Hélène D.
Sainte-Sophie, Québec
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