Period tracker Stardust sends health data to analytics firm, audit finds
5 reported
According to a Mozilla Foundation audit produced in partnership with Harvard's Berkman Klein Center and first reported by the BBC, the astrology-themed period tracker Stardust sends users' reproductive health details to a data firm not named in its privacy policy. Mozilla researcher Shoshana Wodinsky found the app pings third-party trackers from the moment it opens, and when she logged a symptom, the details went to analytics firm RudderStack alongside a persistent user ID with no in-app way to shut the sharing off. RudderStack is built to route data onward to destinations Mozilla could not observe. Stardust also hands Facebook an ad identifier that ties in-app behavior to the platform's existing profiles. The company told TechCrunch it has never received a legal demand for user data. In contrast, the nonprofit-run tracker Euki earned a perfect 10 in the audit, with health data never leaving the phone and features including a PIN, automatic deletion, and a decoy screen.
What’s reported
Stardust scored 2 out of 10 in the Mozilla Foundation audit of six popular trackers.
The app sends birth control type, pregnancy status, moods, and symptoms such as tender breasts and stomach cramps to analytics firm RudderStack.
Stardust also sends Facebook an ad identifier that ties in-app behavior to existing profiles.
Euki, a nonprofit-run tracker, scored 10 out of 10 with no account required and health data never leaving the phone.
Euki's only soft spot is an in-app browser for educational pages that loads web trackers but resets identifiers between visits.
Key figures
Shoshana Wodinsky, Mozilla researcher
Stardust (company, unnamed representative quoted via TechCrunch)
Sources: Wired
