The Privacy Problems Hidden in Your Period Tracker Apps
Mozilla's investigation reveals that popular period trackers like Stardust and Spot On often share sensitive health data with companies like Google and Meta. While some apps like Euki keep data strictly on your device, others send reproductive details to third parties without clear consent. I explore how these apps handle your privacy, the risks of cloud storage, and which trackers you can actually trust to keep your health information safe.
Data collected from a period tracking app can be part of a whole tapestry woven from many different threads of surveillance, and that can be very revealing.
- benoau
This is the second time [1] that analytics in period apps have been problematic, and also follows the recent hack of MixPanel [2] exposing OpenAI usage data. Seems like 3rd-party analytics are becoming a new frontier for security issues.
[1] https://www.thebureauinvestigates.com/stories/2025-09-03/met...
- troyvit
Somebody on HN recommended drip awhile ago:
https://f-droid.org/packages/com.drip/
It's not mentioned in the article.
Like Euki it's local-only. I don't know how they compare as far as features but it's cool that there are two good apps out there.
- bell-cot
Only one (of the six reviewed) that I'd call acceptable -
> Euki is the only app Mozilla recommends without reservations. "Euki is special," Wodinsky* says.
> Unlike the other apps on this list, Mozilla says Euki keeps all your health information stored on your device, without even sending it to the company's servers.
> You don't even need to make an account, so you can stay completely anonymous. Euki also offers a "decoy" feature that shows fake, harmless information if someone gets your phone and tries to snoop.
*Shoshana Wodinsky, a privacy research analyst who tested 6 period tracker on behalf of the Mozilla Foundation
- Cider9986
List of recommended ones: https://www.privacyguides.org/en/health-and-wellness/#menstr...
>Drip, Euki, and Apple Health
- kevin_thibedeau
Whenever this issue comes up I feel the need to relay a story about a meeting with a databroker in 1998 who was tracking menstrual cycles using purchasing records of a wide variety of consumer goods. They will track you to optimize their manipulative, targeted advertising whether you have an invasive app or not.