Sometimes, Facebook isn’t the one you should blame for privacy violations involving Facebook. For example, an investigation by the Wall Street Journal found 11 popular apps that routinely transmit potentially sensitive personal data like body weight and menstrual cycles to Facebook—sometimes in violation of the social network’s own guidelines.
At issue is an analytics tool that Facebook offers to developers called App Events. It’s a plug-and-play SDK that helps developers setup custom trackers of user activity that can translate into ad targeting data. Facebook isn’t the only company offering this kind of tool but according to the Wall Street Journal, it’s been implemented in “thousands” of apps