GPS on the iPhone
The new 3G iPhone’s GPS is only one of several location-finding methods. From Apple’s page:
iPhone 3G uses signals from GPS satellites, Wi-Fi hot spots, and cellular towers to get the most accurate location fast. If GPS is available, iPhone displays a blue GPS indicator. But if you’re inside — without a clear line of sight to a GPS satellite — iPhone finds you via Wi-Fi. If you’re not in range of a Wi-Fi hot spot, iPhone finds you using cellular towers. And the size of a location circle tells you how accurately iPhone is able to calculate that location: The smaller the circle, the more accurate the location.
Location-finding came to iPods Touch and the original iPhone in January: old iPhones can use cell towers, and everything can use Wi Fi, so everything using this platform has at least one option. This is no doubt handy for iPhone application developers using the Core Location framework: they presumably can be agnostic about how location information comes to their app.
Richard notes some potential uses; the iPhone’s camera supports geotagging.
A lot of commentary is suggesting that mainstream GPS manufacturers are shitting themselves in the face of competition from the iPhone — the implication being that a dashboard-mounted iPhone, which could run all sorts of navigation software, would render a Garmin nüvi or suchlike redundant. I’m skeptical of such punditry. My impression is that the GPS marketplace is a lot more specialized than people think — handheld units don’t compete with dashboard navigation systems or geotaggers — so the dashboard systems will likely still be driving people into the river for many years to come.