"Proof Mode" for your Smartphone Camera
ProofMode is an app for your smartphone that adds data to the photos you take to prove that they are real and unaltered:
On the technical front, what the app is doing is automatically generating an OpenPGP key for this installed instance of the app itself, and using that to automatically sign all photos and videos at time of capture. A sha256 hash is also generated, and combined with a snapshot of all available device sensor data, such as GPS location, wifi and mobile networks, altitude, device language, hardware type, and more. This is also signed, and stored with the media. All of this happens with no noticeable impact on battery life or performance, every time the user takes a photo or video.
This doesn’t solve all the problems with fake photos, but it’s a good step in the right direction.