Yeah, and all of that's already true right now because messages are stored on those users' devices already. You'll be heartbroken to hear that those users can also take a screenshot of your disappearing messages and send it to anyone. There are fundamental limitations to what a messaging app can protect you from.
While the analog hole will always exist, and you can't make it actually impossible, Snapchat's quite good at that screenshot thing. Both platforms have APIs to prevent, or at least notify on the use of screenshot. It's weird that signal doesn't use any of them.
i know of ~3 currently working methods to take screenshots on snapchat
it isn't "weird that signal doesn't use any of them" because it does [1] use both, just not for giving a false sense of security to your correspondents
android emulator (i think bluestacks still works), web snapchat client + BetterSnap extension (you can even save the original media file!), on graphene it seems to detect screenshots but not video recording (likely not intentional, there was an open issue to block screenshot detection but no devs were interested iirc)
it's a lost cause except maaaybe provisioning drm keys but even then, as you say, analog hole
re: screen security isn't the same thing - that's what i mean, signal does use those very APIs but not for a half-assed snitching feature
Oh interesting. Yeah, I mean, iOS has the API so it seems silly that they don't do anything about it there, but I guess if you support a diverse userbase like they have to, then user education is impossible and a false sense of security would be a bad thing to give to uaers
