I‘ve been wondering whether the contact tracking features introduced for Covid 19 could be used to verify that pictures of an event where taken by people who were actually around the scene. That way you‘d have some reassurance that a given picture was actually from the event. Combined with pictures from different angles from different people and some kind of verified photography should make alterations harder.
I’m fairly sure that the contact tracing feature has been removed now. And it wouldn’t be needed anyway, the iPhone location services are far more useful. I imagine the geotag could be included with the verification.
Location services is quite hard to trick. To the point people have gone to the lengths of putting iPhones inside a microwave for RF shielding and setting up fake phone tower signals inside to trick the phone in to unlocking the hearing aid feature on AirPods for unapproved countries.
Too much potential for revealing the identities of others there.