I want to buy a wifi-only iPad 2, but it occurred to me that a 3G iPad could come in handy since it would have true GPS. I would use the GPS while visiting countries where I won't have a data connection. My question is, are there any map apps that have the maps locally stored on the iPad so I can use GPS without a data connection? Is there any other way to do that?
Welcome. The WiFi-only iPad doesn't have GPS because the GPS functionality is built into the 3G chipset. 3G and GPS use similar radio frequency (RF) components and, given that this RF circuitry is fairly bulky, it makes sense to combine the two.
In an urban area a WiFi-only iPad can determine its position by reference to a database of WiFi hotspots and base stations. But, out in rural or remote areas, the WiFi-only model will be unable to determine its location.
The 3G model doesn't need to have Internet access - or the 3G function enabled - to use GPS. As you suggest, however, mapping apps, such as the iPad's native 'Maps' app, download maps dynamically on an 'as-needed' basis. So, to use this app, you'd need Internet connectivity even with GPS.
However, some third-party apps, such as TomTom, download all their maps when you install the app, thus obviating the need to have Internet connectivity when using GPS. The disadvantage of these apps is that they cost serious money! The iPad's native 'Maps' app uses Google Maps and the maps are free - but you need Internet connectivity and you are probably paying for the maps to be downloaded on your 3G data plan.
Again - just to be clear - the WiFi-only iPad does not have GPS - you can purchase third-party hardware to enhance the iPad's functionality with GPS capability but the cost of this more-or-less outweighs any advantage you might get from the cost savings of purchasing a WiFi-only iPad.
Whatever you decide, I hope you enjoy your iPad. Don't hesitate to get back in touch with us if there are any other points that require clarification - I have a tendency to 'rattle on' a bit and it doesn't seem to make my explanations any clearer.....
Tim
Scotland