Does anyone know of a service (ideally docker image - probably with app) that can be used to securely share family pictures?
The idea is, that some relatives don't respect wishes of not posting to social media and to prevent this we want to securely share images they can look at but not do anything else with.
Even if I send an image to my mom and she knows not to post anywhere, maybe my aunt wants to see that picture, asks my mom to send it to her and then she posts it, without us knowing.
Probably only works with an app because a browser can't block screenshots.
Is there anything like this out there? Doesn't have to by anything special. Just a web backend for us to upload pictures and a client (probably through a URL) that can then browse them without allowing for screenshots, sharing, downloading, etc
You're basically looking for DRM and I'm not aware of any DRM system that you as a non-media-conglomerate can use.
I'm also not aware of DRM that is actually effective. It's mostly snake oil or, at best, "please don't steal"-signs.
The ultimate Achilles' heel of any DRM system is the analog hole: As soon as the user has an image on their screen, they can take a photo of said screen and share that in any way they want.
As with multi-media piracy, you cannot solve this issue using technology.