Election rigging hit the news recently, with horror stories of the Cambridge Analytica company exploiting data on 50 million people, all from a quiz-master using Facebook. We tell you how that quiz data was used to produce psychographic profiles whose tentacles stretched back into Facebook’s huge database of links and Likes. How it was made ready for manipulation of behavior in key votes and referendums. Has social media therefore become a hidden surveillance state? Which apps on Facebook might already have your data and be threatening your privacy? Find out how to check and what you can do about it!