This is a seldom known fact that catches people out because most assume that if you have the map locally, it will help you traverse it locally. My personal story on this is going across the border to see an NFL game in Detroit last year, turning off data because of the usurious rates Canadian carriers charge for roaming. When leaving I couldn't navigate at all -- despite the relevant map being available -- so I had to turn data on for a couple of seconds just for Google to get the route. $20 for 3MB of data. Someone relying upon it when they're out of cellular range would be in a much worse situation.
You know, people did manage to navigate before the advent of GPS based navigation systems. They looked at a map, planned out their route, watched for the appropriate streets, and if they got lost, stopped and looked at the map again.
If you have the offline map, you can still do this even if you can't use the GPS navigation feature.
No kidding. Thanks for sarcastically pointing out the obvious.
I can make coffee by pounding my own grinds and boiling water over a campfire. But if I wake up expecting to turn the coffee maker on and can't, it can throw off my day. Further Google Maps is a terrible, terrible way to handle navigate on a smartphone, especially in a dense urban area with layers of highways.
Apologies for the sarcasm. I was merely trying to point out that navigation may not be worth the ridiculous roaming charges, and instead just using it as a static map is possible.
If you can find Wifi, that will also provide the necessary connectivity to enable your navigation route to be downloaded. This is how I got around rural Nevada, Utah, and Arizona with my Galaxy Nexus.
