You knew this day would come: you can now upload images to Flickr from a location enabled device and Flickr will take care of the geocoding. ZoneTag works by using cell tower information:
ZoneTag can automatically tag your photos with the location, based on the cell tower, in which they were taken. The location of the cell tower is not known until our user community updates the city, state, or zip code of their photos on Flickr. ZoneTag is then able to map the cell tower to the location.
on the following phones:
Currently, ZoneTag only works on Nokia Series 60 phones. ZoneTag is known to work on 6620, 6670, 6680, 6681, 6682, 7610 models, and it is likely to work on 3230, 6630, 6260 as well.