This is why you should always read the terms and conditions of an app. I'm always shocked at how many people do not take this seriously. In this age of "data sharing" it is super important to take extra caution.
That's not a solution. T&Cs are written as vaguely as possible to permit as much flexibility as possible, and nothing stops a malicious actor from violating their public privacy claims.
It may not be a solution, but it's a smart thing to do and at least a step in the right direction, no?
Not really. I tend to skim T&Cs and virtually every one I've seen has language that would probably permit this sort of behavior.