Geolocation by GPS my be the most straightforward approach, but we mustn’t forget the other ways to get lat/lon coordinates.
All current cell phones support aGPS positioning to comply with federal E-911 mandates, but not all phones make it easy for the user to get that information out of them. Still, some do and GPS-enabled moblogging is becoming common in Asia and Europe, and there’s at least a public proof of concept going in the US.
Then there’s ethernet/WiFi. Plazes is a kind of social networking application that allows users identify their location based on their network fingerprint. Using the assumption that networks are typically stationary, Plazes then associates lat/lon coordinates to that network based on information submitted by user who ‘discovered’ the network. Plazes’ real trick, however, is to show me who else is online nearby. Problem is, I live and work in New Hampshire where I appear to be the only user online north of Virginia.
But the Plazes folks didn’t invent the concept of using network information to identify location. If I wasn’t so lazy I’d find the story I read a couple of years ago that mentioned it, but this June 2004 article in New Scientist tells the story of one such effort: PlaceLab (extra coverage at Engadget and ExtremeGPS). A Google search turned up Herecast and now Engadget is reporting on AllwaysOnGPS, a replacement GPS driver (for Windows PCs) that mixes GPS and WiFi derived location data to provide the most accurate info despite changing coverage.
Finally, one of my favorite solutions is to use Earthcomber in manual mode. The Palm application allows you to scroll around a map and mark locations as though they were waypoints in a GPS. And though that’s neat, it’s the mapping features that make it a winner. It’s far better than those lousy tourist guides in cities. I used to go to AAA for maps and guides in preparation for a trip, but now I check Earthcomber for area maps and updates.