Over the weekend, Yahoo released some interesting alpha geotagging software called Zonetag. It's built for Nokia S60 mobile phones and automatically tags photos with the location where they were taken according to info from the cellular towers the phone was connected to at the time. Photos are then sent to Yahoo's photo sharing site, Flickr. It's an interesting proof of concept, but will need to support more phones to get traction in the US. It also doesn't do that great of a job actually pinning down the location, but according to the site the quality will improve with as more people use it.
We tried Zonetag out on a Nokia N70 and were unable to get it to work. The official FAQ lists a handful of phones, but nothing in the N series despite being the latest S60 devices. It did work on a 6682 that we tested which is on the list. Photos can be uploaded with custom tags and privacy settings--either private (default) or public. Private photos can further be protected by limiting access to friends, family or no one.
The location data is provided in the form of a cellular id, a specific number that each tower is assigned. As Yahoo puts it,
We use two methods to learn the actual location (city, state, zip code) that correlates with that cellular ID. First, if you use ZoneTag with a Bluetooth GPS device, the GPS coordinates of the photo will be uploaded as well as the cell ID. We are now able to learn that this cell ID corresponds to the city, state and zip of those GPS coordinates. Subsequently, if another photo is uploaded with the same cell ID, we will be able to associate the correct city, state and zip code tag to that photo.