The coordinate nobody looks at
Phones write a metadata block alongside every photograph. The format is Exif, standardised by CIPA and JEITA as DC-008, and among the shutter speeds and camera models it has room for the position of the shot, held in fields named GPSLatitude and GPSLongitude and accurate to a few metres. Whether they are filled in comes down to one permission.
Check it yourself
Nothing needs installing. Open a recent picture in the Photos app on an iPhone and swipe up; a small map underneath means the coordinate is attached. Google Photos on Android puts the same thing behind the info button, and the fields it reads are exposed by a system class called ExifInterface, whose documentation lists the GPS tags one by one.
Why this lands harder on dog owners
A dog gets photographed wherever the dog happens to be, which is disproportionately the sofa, the garden, or the pavement immediately outside. What matters is not the single picture but the pile of them. There is probably one photograph of your front door in existence and several hundred of your dog, and once the coordinates are plotted the densest cluster is where you sleep.
Shared GPS routes converge on the same address by a different mechanism, which a companion article deals with separately.
Uploading is not stripping
Some services discard metadata when a file arrives and some pass it straight through, and there is no way to tell which from the outside. Test the file rather than the promise. Upload one picture, fetch back the copy the service hands out, and inspect that copy instead of your original.
Where switching it off stops helping
Revoking the camera's access to your location only affects photographs taken afterwards. Everything already in the library keeps its coordinate, and copies are quite possibly sitting in a cloud library too.
Metadata is also only half of it. A house number behind the dog, a street sign at the edge of the frame, or the building opposite will lead somebody to the same address without any file inspection at all, and a shot through a window often gives away enough through the direction it faces.
What Barnaby does with an uploaded picture
Every selected image is re-encoded on the device before it goes anywhere, scaled down to display size and written back out as a JPEG. Because the file is rebuilt from decoded pixels, none of the original Exif block survives, the coordinate included. Profile and dog pictures abandon the upload outright should that step fail, rather than quietly sending the untouched original; a photo in a post (walk or photo post) does send the original in that case; the failure is reported to our error monitoring (Sentry), not shown to you. Section 7 of the privacy policy sets this out.
If your own phone can draw a map from a photograph, assume the person you send it to can as well.
