Best Period Tracker Apps for Android (2026 Picks)
Period tracker apps collect some of your most personal health information — cycle dates, symptoms, moods, sometimes pregnancy status and sexual activity. Research from 2025 found that around 70% of these apps share personal and sensitive health data with third parties. So for this category, privacy is not a nice extra — it is the first thing to check, before you even look at features or design. This guide compares the best period tracker apps for Android on features, price, and privacy. We also flag two popular apps worth avoiding after they failed Mozilla's 2026 privacy tests.
Quick Comparison
| App | Price | Play rating | Privacy score (Mozilla 2026) | Best for |
|---|---|---|---|---|
| Flo | Free / ~$40-60 per year | 4.72 (5.1M reviews) | 7/10 | Health education |
| Clue | Free / ~$40 per year | 4.49 (1.5M reviews) | 8/10 | Science-first tracking |
| Euki | Free | 3.67 (351 reviews) | 10/10 | Maximum privacy |
| Drip | Free | — | Local-only | Open-source tracking |
| Periodical | Free | — | Local-only | Simple Android-only |
| Ovia | Free / employer plans | — | Owned by Labcorp | Trying to conceive |
| Natural Cycles | ~$150 per year | — | Strong | FDA-cleared birth control |
1. Flo — Best for Health Education
Flo is the most downloaded women's health app in the world — ~380 million downloads and 68 million monthly users. It tracks periods, ovulation, PMS symptoms, mood, sleep, and more, and packs thousands of health articles, an AI symptom assistant, and anonymous community chats.
The free tier works for basic tracking but comes with ads and constant upsell prompts. Flo Premium (about $40-60/year depending on the offer) removes ads and adds personalized insights, detailed pregnancy tracking, and cycle reports. One honest note: Flo settled with the FTC in 2021 over sharing health data without consent. Mozilla's 2026 testing found that declining Flo's optional analytics settings now keeps health data away from advertisers, and its Anonymous Mode hides your IP address — but it remains the most data-hungry tracker on this list.
2. Clue — Best for Science-First Tracking
Clue is the clinically minded, Germany-based tracker recommended by the American College of Obstetricians and Gynecologists. It is gender-neutral in design, explains how its predictions work, and lets you track over 200 factors — mood, energy, sleep, pain, sex drive — to spot real patterns.
Privacy is a genuine strength: GDPR-compliant, no data sales, and granular controls that let you separately opt in or out of research, analytics, and advertising data use. Clue Plus (~$40/year) adds pregnancy mode, wearable sync, and deeper insights. On the free tier, expect frequent full-screen upsell prompts.
3. Euki — Best for Privacy
Euki earned the only perfect score (10/10) in Mozilla's 2026 privacy investigation. It is a nonprofit, open-source app that stores everything on your device — no account, no cloud, no trackers, no third-party data sharing at all. It even includes a duress PIN that shows a fake screen if someone forces you to open the app.
The trade-offs: locally stored data cannot be recovered if you lose your phone or forget your PIN, and with only a few hundred Play ratings (3.67 stars), it is a niche app without Flo's polish. But if privacy is your top priority, nothing else comes close.
4. Drip — Best Open-Source Alternative
Drip is a non-commercial, open-source project that keeps all your data on your device, like Euki. It is transparent about how it computes predictions, lets you lock the app with a password, and uses a gender-inclusive design without the typical pink palette. Available on Google Play and F-Droid. A great choice if you want Euki-level privacy with a slightly different interface.
5. Periodical — Best Simple Android Option
Periodical is Android-only, free, open source, and minimalist: it stores everything locally and contains no third-party analytics or ad trackers. It calculates fertile days and tracks menstrual symptoms. Keep in mind it uses the Knaus-Ogino calendar method, which is not a reliable form of contraception — for that, look at Natural Cycles below and talk to a clinician.
6. Ovia — Best for Trying to Conceive
Ovia Fertility is purpose-built for conception: BBT charting, cervical mucus logging, ovulation test results, and a daily fertility score. It is free, often through employer health plans, with good educational content for the trying-to-conceive journey. The honest caveat: Ovia has been owned by Labcorp since 2021, and employer-sponsored versions can access de-identified employee health data — check your plan's terms.
7. Natural Cycles — Best FDA-Cleared Contraceptive App
Natural Cycles is the only FDA-cleared birth control app. It uses a temperature-based algorithm with a daily green/red day status (93% typical-use effectiveness) and includes a basal thermometer with the subscription. It costs about $150 per year and only suits people with relatively regular cycles who will measure their temperature daily. This is a real contraceptive method, not a calendar estimate.
What About Stardust and Period Calendar?
Two popular apps deserve warnings, not recommendations. Stardust (2/10) was caught sharing birth dates, birth control methods, pregnancy status, reproductive goals, and symptoms with analytics firm RudderStack. Period Calendar (6/10), the only ad-supported app Mozilla tested, sent device details to Google and InMobi advertising services the moment it opened. We list them so you know to avoid them.
How to Choose
Before picking, it helps to know what kind of tracker you actually need. The apps above split into three camps, and each suits a different person.
If privacy is non-negotiable
Choose Euki or Drip. Both store everything on your phone — no account, no cloud, no analytics SDKs phoning home. The price of that privacy is convenience: no automatic backup if you lose the phone, and fewer polished features than the big commercial apps. A few habits help: turn on the app PIN if offered, decline every optional analytics toggle, and export or delete old data periodically so the app holds only what you need.
If you want predictions you can trust
Choose Clue. Its strength is science — transparent algorithms, medically reviewed content, and an endorsement from the American College of Obstetricians and Gynecologists. It takes a few months of consistent logging before its predictions become accurate, so stick with it. The free tier is generous for basic tracking; pay for Clue Plus only if you need pregnancy mode or wearable sync.
If you want education and community
Choose Flo. No other app matches its library of health articles, symptom checker, and anonymous discussion forums. Just know what the free version costs you: ads between screens, constant upsell prompts, and the most data-hungry tracker on this list. If you go premium, the annual plan (usually $40-60 with promotions) is far better value than the $11.49 monthly option.
- Privacy first: Euki or Drip — data never leaves your phone.
- Science and predictions: Clue — transparent algorithms, strong GDPR protections.
- Learning and community: Flo — unmatched health library, but watch the free-tier ads.
- Trying to conceive: Ovia — built for fertility tracking.
- Hormone-free contraception: Natural Cycles — FDA-cleared, but requires daily discipline.
A Medical Note
This article is for general information only and is not medical advice. Period tracking apps are not a form of birth control (except FDA-cleared Natural Cycles, used exactly as directed) and do not protect against STIs. A tracking app is also only as accurate as the data you enter — forgetting to log periods or symptoms leads to wrong predictions. And even the best app cannot diagnose conditions like PCOS or endometriosis; if something looks consistently off in your cycle history, show that history to a clinician rather than letting the app interpret it. If you have irregular cycles, concerning symptoms, or contraceptive needs, talk to a qualified healthcare provider rather than relying on an app alone.
FAQs
What is the most private period tracker app?
Euki. Mozilla's 2026 privacy investigation gave it the only perfect 10/10 score because it stores all data locally on your device, requires no account, and shares nothing with third parties. Clue came second at 8/10.
Is Flo safe to use for period tracking?
Flo settled with the FTC in 2021 over sharing health data without consent, but Mozilla's 2026 testing found it now keeps health data away from advertisers when you decline optional analytics settings. Its Anonymous Mode also hides your IP. The free tier has ads and upsell prompts.
Can a period tracker app be used as birth control?
No. Period tracking apps are not a form of birth control and do not protect against pregnancy or STIs. Only Natural Cycles is FDA-cleared as a contraceptive method, and even that requires careful daily tracking.
Are period tracker apps free?
Most have free tiers with paid upgrades. Flo Premium costs about $40-60 per year, Clue Plus about $40 per year, and Natural Cycles about $150 per year. Euki, Drip, and Periodical are completely free with no paid tier.
Do period trackers sell my data?
A 2025 study found about 70% of period tracker apps share personal and sensitive health data with third parties. Apps like Euki and Drip store data only on your device, while apps like Clue and Flo store data in the cloud and offer varying privacy controls.