Lifehacker61%
This Period-Tracking App Actually Keeps Your Data Private 80%
By Beth Skwarecki30%
7/20/2026, 8:30:00 PM
BS Summary: This article contains 25 faulty reasoning types, including Appeal to Authority, Hasty Generalization, and Halo Effect, with Negativity Bias as the most egregious example at 22.9% saturation with 106 hits. Analysis detected 1,001 faulty-reasoning hits from 462 analyzed words, generating a BS Score of 72.2% and a BS Rank of 80% (3,913 of 18,943 articles). This article is worse (more manipulative) than 79.30% of the article peer group.
Period tracking is a simple job that plenty of apps can do.
But most apps these days-including those that track health data-store information about you on their own servers and sometimes even share that data with advertisers.
The Mozilla Foundation has tested several of the most popular period-tracking apps, and it identified one as better than the rest at keeping your data private: Euki.
Privacy is especially important for period trackers in light of the political and legal battles that surround abortion and birth control.
We know that police have used other data, like messages and search history , to prosecute people for alleged abortions.
It's understandable if you don't want tech companies to keep or share data about your reproductive health.
Our sister site PCMag has a guide here to tracking your period privately .
They recommend Apple Health or DIY methods like coded notes on a calendar.
Recently, the Mozilla Foundation did a privacy audit of six of the top period tracking apps .
It found serious privacy flaws in Stardust, SpotOn, Period Calendar, Flo, and Clue, but held up Euki as the best of the bunch: "We strongly recommend Euki for anyone who puts privacy first."
How to install and use Euki privately
Euki is available for both iOS and Android .
The app is free, with no in-app purchases, and the Apple App Store reports that the developer does not collect any data from the app.
You don't need to create an account to use the app; it starts working as soon as you install it.
Most importantly, your data is stored locally on your phone and not sent to any servers.
Most period-tracking apps, including the more privacy-focused ones that say they encrypt or anonymize your data, still store your data on servers that the company has access to.
Some say they would fight a subpoena if they were asked to hand over data; but it's probably better not to give your data to a company in the first place.
Euki has a few other privacy features.
You can set a PIN when you install the app, and a fake PIN that will hide your data.
(When I enter the fake PIN, I get a message that the app is having technical difficulties and I should try again later.)
You can tell Euki to delete your previous data, either by tapping a button in settings or by setting up a schedule to regularly delete old data.
As for the app's features, you can log just about anything to a given day.
There are categories for bleeding, emotions, body symptoms, sexual activity, and more.
You can track appointments and even things like when you check the strings on your IUD.
Analysis
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