Most cell phones don't keep maps in the phone itself, they download the maps as needed. This is OK for folks who only need GPS in urban areas or on major highways where there is almost always digital data coverage.
If you need GPS off the beaten path where there is no data service the phone GPS reverts to lat/long data.
I'm sure this will be resolved at some point in the nearish future. Flash memory is getting so cheap there will soon be room in the phone for plenty of preloaded maps. But without all maps preloaded on the phone I'd be wary when riding where I sometimes go.http://www.kawasakiversys.com/forums...itpost&p=57237
The other issue is whether or not you need your GPS to be waterproof. My cell phone works great as a GPS, but rain would destroy it.
I have a Garmin 2720. I'm considering using it on the bike, and using my cell phone GPS in the car.
I should add that I have an LG Dare under Verizon, and I have tried the GPS (VZ navigator) on a one month trial basis. My daughter has an LG Env2, also under Verizon, and she had VZNavigator all summer. She did really well using VZNavigator, although she had no point of comparison. I found that VZ Navigator was 90% as good as my Garmin for navigation, and otherwise better because the service includes traffic updates (Extra cost service from Garmin IF you have the right hardware, and I don't have that hardware.), the maps are always up to date (My Garmin costs over $60/year to buy new maps, so my maps are 1 or 2 years old most of the time.), and up to date listings for store, restaurants, and the like. The VZNavigator under Verizon was $10/month with no extra charge for navigation data. There is a charge for data if you have no data plan only for the download of the VZNavigator application.
Originally Posted by healdem
I'd be very surprised if the Iphone has an inbuilt GPS receiver
In the US phones have been required to have GPS chips for a several years now, supposedly to allow emergency services to find you more easily if you need help (I think it's more big brotherish than that.) In the latest generation of phones there are applications, like the GPS programs, that allow you the phone owner to access the GPS.