A research project downloaded a bunch of pictures of cats, and put the photos on a map by using the GPS metadata.
Use the Photo Investigator app to see if your iPhone/iPad photos have GPS coordinates in them, or to remove the GPS location from your photos before posting them (Facebook removes the GPS coords, but G+, Flickr, and Pinterest don’t)
Here’s “I Know Where Your Cat Lives“
The Photo Investigator App makes viewing, editing, removing and sending photo metadata easy. Photo and video metadata may include location (if added by the camera), date, device, software versions, file size, file name, an “iOS Metadata” section, and many more metadata items. more. Users can view and share DEPTH MAPS by selecting a portrait photo and tapping “Portrait”.