to Facebook”
A number of commonly used menstrual apps automatically send user data to Facebook. This is done on Android via Facebooks sdk, even if a user does not have a Facebook account or does not have the Facebook app on the phone.

This concerns various apps that have been downloaded millions of times, according to research by Privacy International . The privacy organization looked at the Maya, MIA, My Period Tracker apps from Linchpin Health, Ovulation Calculator, Period Tracker from GP International and Mi Calendario. Of those apps, only Period Tracker does not send any information to Facebook. The applications are used to monitor menstrual cycles, but often also to monitor fertility periods. This is useful for couples trying to conceive. This requires a lot of sensitive information to be collected, such as how users feel physically, but also when they have had sex.

The other apps all use a feature from Facebook’s Software Development Kit, which can be used for various purposes. One of those goals is to collect data for displaying more personal advertisements. The Privacy International study shows that most Menstrual Apps Send data to Facebook that users enter themselves. In some cases it is about detailed information, such as the content of notes that users can take, but more often it is about metadata. For example, the Maya app gives a variable figure to the ways in which a user has sex. When using contraception, for example, it gets a 2, for unprotected sex a 3. That variables are then shared with Facebook. Dates, such as when a menstrual cycle has started, are also sent to Facebook in this way.

According to Privacy International, it is by no means clear to users which data is shared with whom. Some apps already send data to Facebook as soon as the app is opened. So that happens before users can even accept the terms and conditions, the researchers say. That would be against the AVG. Facebook says in a response to BuzzFeed that apps should be clear about what data they collect.