Mozilla Finds Stardust App Shares Sensitive Health Data with Analytics Firm

Mozilla research shows Stardust shares users' health data with an analytics company.

The Stardust period tracker app has come under scrutiny after Mozilla research revealed that it shares sensitive users' health data with Mixpanel, a third-party analytics company. This finding highlights potential privacy risks in reproductive health apps, especially amid heightened concerns since the 2022 overturning of Roe v. Wade, which caused a sharp increase in users seeking privacy protections.

Stardust experienced a 4,400% increase in downloads in June 2022, reaching roughly 200,000 daily installs as its users hoped for secure data handling. However, TechCrunch analysis at the time found the app shared personal data such as phone numbers and device information with Mixpanel. Stardust's privacy policy acknowledged collecting device, activity, and location data and disclosing de-personalized data to providers or when legally required.

In August 2022, Mozilla's Privacy Not Included report flagged Stardust along with 17 other reproductive health apps for unclear privacy policies and data-sharing practices. Rachel Moranis, Stardust's founder, noted that the current app version disabled or removed certain Mixpanel data collection features present in older versions.

These developments underscore the ongoing regulatory and compliance challenges faced by app developers handling sensitive health data. Legal and privacy professionals need to closely monitor such apps to ensure they align with evolving data protection standards and user expectations.

Yes, but: Stardust's founder claims the latest app version disabled or removed problematic Mixpanel data collection mechanisms, suggesting some privacy improvements.