I think I finally understand what the point of Facebook apps is and why they've always felt in some way dodgy. It's been clear for years that Facebook apps can

I think I finally understand what the point of Facebook apps is and why they've always felt in some way dodgy. It's been clear for years that Facebook apps can get your user data, and that of your friends, and that Facebook designed them that way and were aware of that. The Guardian article even mentions that one of the apps used by GSR to gather data for Cambridge Analytica triggered Facebook security protocols trying to pull too much data. What I didn't understand is why Facebook would grant this - maybe at some point they needed viral apps on the platform and giving user data away encouraged people to make them - but why did it still work a few years ago? But this article made it click: all you can really do to monetise or use millions of profiles of Facebook users is target them with ads, and Facebook is the only place you can target those ads effectively given Facebook user data, and the more data you have the more effective those ads are, the more you pay Facebook. Facebook don't sell user data, they've long said that - and it's true. They sell the ability to target advertising to their users, and you can do that a whole lot better if you have their user data. So they don't sell it, they give an API for their users to freely give it away, knowing that once you've done all your analysis on it you'll conclude that you should spend money paying Facebook to actually deliver your messages to those users.