> we immediately banned Kogan's app from our platform, and demanded that Kogan and Cambridge Analytica formally certify that they had deleted all improperly acquired data. They provided these certifications.
To generalize the issue, if you were in charge of APIs at some company A and some company B (not necessarily located in your jurisdiction and not necessarily subject to the same legislative framework as you) told you they used to have the data, but deleted it since then, what additional measures would you recommend company A pursue?
Zuck's announcement seems to have a decent outline -- start with investigating apps with access to large amounts of data, audit apps with strange behavior. But after a year, after the CA (and other) controversies are forgotten, what I was thinking was that FB should be doing regular, random audits/investigations, and publicize the punishment.
I don't mean identifiable shaming, e.g. "Last week, we banned Jane Smith and her Flappy Farm app for misusing the data of 3,000+ users". But maybe weekly/monthly tallies of apps that were shut down or sanctioned, and a breakdown of the reasons why, and users affected, etc. Every once in awhile, an app maker might post a "We Fucked Up" article on HN, which helps even more in reminding people of TOS.