If you have a period tracker on your phone, it’s probably one of your most used apps. 

In a world where it's hard to take a moment for yourself between work, keeping up with friends and social media, having something to track your period can be quite handy. It tells you important information about your period and calculates when it is next due.

They’re some of the most popular apps out there, but it seems that the companies responsible for these apps could be selling off your personal data for profit. 

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A Brazil-based cyber security guide, Chupadados powered by the female-led think tank Coding Rights, recently did an investigation into just what you’re saying yes to when you click on the “I agree” option under these apps’ terms and conditions. 

In their investigation, Chupadados focused on four of the most popular period apps out of the more than 200 that are available on app stores. These four are Glow, Clue, My Calendar and Maya. They studied each company’s privacy policy and found that “all of the apps rely on the production and analysis of data for financial sustainability.”

Kara Maria Ananda notes how she got an email from a period tracking website asking her to promote their information within her community and she was shocked to find that they were tracking hundreds of women’s fertility information every month. 

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This article in The Guardian lists exactly what and how Facebook and Google knows about you and how they use that personal data to show you ads. Many other apps including the ones you use to track your period are using the same model as all the information we put online becomes something valuable for companies to use. 

According to Chupadados: “if we consider the time that we spend feeding social networks and apps with information as time spent working, the 1 billion Facebook users worldwide are carrying out over 300,000,000 hours of unpaid work per day.” 

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Basically they’re making money by you sending emails, liking that picture and saving what your period is doing because they sell off that information to other businesses who then target specific ads to you and tell their sales and marketing teams about your needs. 

If you’re thinking “how bad could this really be? What would they really do with that information?” there are downsides to having your sensitive information floating around, Chupadados warns, “It is worth remembering that the more data collected about us, the more vulnerable we become. We are exposed not only to ceaseless propaganda, but also to potential leaks of our intimate information.” 

Glow, one of the apps studied in Chupadados’s report, had a problem (which they fixed by updating it) in 2016 where anyone who knew a user’s email address could access that user’s personal data according to an investigation by Consumer Reports. Which is quite a big deal since Glow asks for things like when last you had sex and in what position, how many drinks you’ve had every day and when you get your period. 

So be careful with your period app, or consider downloading a different one that uses less of your information.

And think about what details you're sharing with other types of apps you use.

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