- Ahh... so it didn't do dual data and voice, the maps were pre-downloaded.
Google did that a while back... when you plotted your route, it downloaded all of the data that it needed to get you to your destination, then only needed a data connection if you changed your destination or went off the path and it had to re-route.
Now you have the ability to pre-download parts of the map for offline use. I'm not sure if it's gone further than that at this point. I have admittedly not paid as much attention lately.