"Snap a photo of a sunset with your iPhone and you can upload it to Twitter with a few clicks.
But your smartphone might be transmitting more than a pretty photograph. It could be collecting and storing data about your real-time location – and then broadcasting that information when you upload photos onto the Internet...
In Cybercasing the Joint: On the Privacy Implications of Geotagging, two researchers from the University of California Berkeley investigated how different websites incorporate geotagged media. By examining photos and videos on Flickr, Craigslist and Youtube, they found 1.3% to 4.3% of uploaded media included embedded location data. Not surprisingly, they found geotagged photos and videos were most often captured through high-end cameras and smartphones (rather than basic cell phones)."