This weekend I was out in the country and using Google Navigation on my TBolt to find my way around. My GPS locked quickly and I never lost the signal, however I did move into an area with no data coverage. Navigation stopped working at that point with a message that the data connection was lost. I was under the impression that, like with a stand alone GPS, only GPS was needed for Navigation, not internet. Is this a known issue and does anyone know a way around it?