Popular period-tracking apps were found sharing extremely sensitive data to Facebook, including when users last had sexAn investigation from privacy advocacy group Privacy International found that period-tracking apps downloaded by millions of users shared alarmingly sensitive data with Facebook and other third-parties, including users' drinking habits, medical symptoms, and when they last had sex.
Privacy International's report identified five apps which shared data with Facebook. It focused on two apps in particular — Maya and MIA Fem — which the report said were sharing alarming amounts of detail.
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Both apps had Facebook's Software Development Kit (SDK). SDK lets apps use certain features, for example allowing users to log in via Facebook, and helps the apps manage their data. In return, the apps feed data back to Facebook.
Privacy International's analysis showed that both apps started feeding data back to Facebook even before users agreed to its privacy policy.
Once users start using the apps, incredibly specific and sensitive information was also passed along. Both apps shared data to other third-parties as well as Facebook, Privacy International said.
The details of this are lurid enough, but for those - like me - to whom the actions of these specific apps don't apply, there's still something worth knowing, which I emphasized. If you use some other app, like, hypothetically, MapMyRun, that let you login via FB, information about your activities you track using it might be shared in the background to FB.
I do not know whether MapMyRun does this, but they do let you login via FB. And if FB gets info, they use it to target ads. Those ads don't control what you do, but they do entice certain purchases and actions based on personal information users might have thought private.
