The guide

Period tracker apps compared: which ones keep your data private

Ten period and fertility apps, checked against their own privacy policies, help pages and prices.

Checked November 11, 2026

A period tracker holds some of the most personal data on your phone, down to when you have sex and when you might be pregnant. This guide looks at who else can see that data in ten popular apps, and what each one costs.

Every fact here comes from the company's own pages: its privacy policy, help center, product pages and app store listing for prices. If a company doesn't say something, we left it out instead of guessing. Public records, such as FTC settlements, are linked to the source. Prices are in US dollars from the US App Store or the company's site on the date above, and they change often.

Barkat is made by the same people who publish this guide. We held it to the same rule as every other app, and each section below says where other apps do more.

Our pick

Our pick for most people who want privacy is Barkat. It needs no account or email, keeps your entries in your browser, and has no ads, trackers or analytics. If you turn on sync, your data is locked on your device with a six-word phrase before it's sent, so our server can't read it. It's free, and it charts BBT and cervical fluid along with your period.

Barkat is not birth control, and its predictions are estimates. If you want an app to prevent pregnancy, look at Natural Cycles, which is FDA-cleared as contraception. Pick Apple Health if you live on iPhone and want end-to-end encrypted sync from a large company, drip if you want open source code you can check, and Clue if you want research-backed articles alongside your tracker.

Who can read your cycle data

Almost every app says your data is encrypted. That usually means it's scrambled while it travels and while it sits on the company's servers, and the company holds the key. Its staff, its contractors, and anyone with a legal order it has to obey can still get at it.

End-to-end encryption is different. The data is locked on your device with a key only you have, so the copy on the server can't be read by the company. Apple Health (with two-factor authentication on) and Barkat's sync work this way. drip goes further and keeps no server copy at all.

Two other things matter:

Advertising and analytics tools. Several apps share device IDs and app events with ad platforms such as Meta, TikTok or Google, even when they promise not to share health data. Those IDs can still show that you use a fertility app.
A lost key can't be reset. If only you hold the key, losing your phrase or password while no device is still signed in means losing the synced copy.

Quick picks

No account, no ads or trackersBarkatRuns in your browser, with optional sync locked by a six-word phrase.
Birth controlNatural CyclesFDA-cleared as contraception. Paid subscription.
iPhone and Apple WatchApple Health Cycle TrackingBuilt in, and synced data is end-to-end encrypted with two-factor authentication.
Open source, data on your phone onlydripFree, no data collected, symptothermal charting.
Trying to conceive with BBT and OPKsFertility FriendDetailed charting, no ads or third-party analytics.
Reading about your cycleClueLarge library of research-based articles.

Side by side

App	Price	Account needed	Locked so the company can't read it	Sells or shares for ads
Barkat	Free; Premium $9 once from 2027	No	Yes, synced copy	Neither
Flo	Free; Premium subscription	Yes, or Anonymous Mode	No end-to-end claim	No sale; IDs to ad tools
Clue	Free; Plus $39.99/yr	Yes	No end-to-end claim	No sale; IDs to ad tools
Natural Cycles	$149/yr or $21.99/mo	Yes	No end-to-end claim	IDs to ad partners
Stardust	Free; All Access subscription	Yes	No end-to-end claim	No sale; tracking IDs
Apple Health	Free with iPhone	Only for iCloud sync	Yes, with two-factor	Apple can't read it
Ovia	Free	Yes	No end-to-end claim	No, since June 2025
Premom	Free; paid Premium	Yes	No end-to-end claim	Marketing use; FTC 2023
Fertility Friend	Free; VIP $45.99/yr	Email	No end-to-end claim	Neither
drip	Free	No	No server copy	Neither

01Barkat

Price: Free; Premium $9 once from 2027
Account needed: No
Where data lives: Your browser
Locked so the company can't read it: Yes, synced copy
Sells or shares for ads: Neither
BBT and fluid: Both
Birth control: No

Barkat is a web app with a cycle calendar, a BBT chart and a few things most trackers don't have: moon phase, tithi and nakshatra, a Vedic birth chart and a tarot deck. You open it in any browser and can add it to your Home Screen.

Privacy: No account or email. Your entries are saved only in your browser. Sync is optional and uses a six-word phrase instead of a login. Your data is locked on your device (AES-GCM) before it's sent, and the server never stores the phrase, so Barkat can't read the synced copy. Nobody can reset the phrase, so keep the card it gives you. The site has no ads, trackers or analytics, loads nothing from third parties, and says it will never sell your data.

There is one exception you choose: the optional private calendar link for Google or Apple Calendar is not locked, because the calendar app has to read it. Anyone with that link can see it, and you can replace or delete it at any time.

Tracks: Period, predicted ovulation (15 days before your next period), fertile window, BBT with the 3-over-6 rule and a coverline, cervical fluid, resting heart rate, notes and a year view. Export is a CSV spreadsheet.

Best at: Tracking with no account and no one else able to read your data.
Missing: Barkat is not birth control and its predictions are estimates; Natural Cycles is the one to look at for FDA-cleared contraception. There's no LH test logging, which Flo, Premom and Fertility Friend have. There's no App Store or Google Play app. It's new, so it lacks the years of research behind Clue and Natural Cycles.
Price: Free. Premium (birth chart and dashas, cycle history older than three months, extra wallpapers and card backs) is free for everyone through the end of 2026, and stays free for good for anyone who starts before then. After that it will be $9, paid once, not a subscription. An iPhone app is coming in 2027, and Premium carries over to it at no extra cost.

Sources: Barkat privacy · Barkat home page

02Flo

Price: Free; Premium subscription
Account needed: Yes, or Anonymous Mode
Where data lives: Flo's servers
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: No sale; IDs to ad tools
BBT and fluid: Both, plus LH tests
Birth control: No

Flo is one of the most downloaded period apps, on iPhone, Android and Apple Watch. It covers period and ovulation predictions, pregnancy and a large health library.

Privacy: Flo's policy says it will never sell your data and does not share health data with third parties for marketing. With your consent, it shares device identifiers, your age group, subscription status and app launches with AppsFlyer, Firebase and TikTok Ad Manager to measure its ads. Data is encrypted in transit and at rest on Flo's systems; Flo doesn't describe end-to-end encryption.

Anonymous Mode lets you use Flo without linking your email, name or other identifiers to your account. Flo says some features, such as wearable integration and some notifications, won't work in it, and support may not be able to help with account questions.

In 2021 Flo settled with the FTC over allegations that it shared users' health data with Facebook, Google and others after promising to keep it private. The order requires consent before sharing health data and an independent privacy review.

Tracks: Period, fertile window and ovulation predictions, LH test results, BBT and discharge. Flo says it is not a method of birth control.

Best at: LH test logging and a long list of symptoms, with an anonymous option.
Missing: An account and a server copy Flo can read. Barkat and drip work with no account at all.
Price: Free. Flo Premium is a monthly or yearly subscription; the US App Store lists Premium options up to $59.99.

Sources: Flo privacy policy · Flo Premium · Flo on the App Store · FTC: Flo Health order (2021)

03Clue

Price: Free; Plus $39.99/yr
Account needed: Yes
Where data lives: Clue's servers, EU
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: No sale; IDs to ad tools
BBT and fluid: Discharge; BBT in one mode
Birth control: Logs your method

Clue is made by BioWink in Berlin and runs on iPhone, Android and Apple Watch. It's known for its articles on cycles, hormones and health, written with researchers.

Privacy: You need a free Clue account, made with email or an Apple, Google or Facebook login. Data is stored on Amazon servers in the EU, and Clue says it encrypts it there. Clue doesn't describe end-to-end encryption. It says health data is never shared with or sold to advertisers. If you agree in its privacy settings, it shares device IDs and events like installs and subscriptions with Adjust, which passes them to ad networks such as Meta and TikTok. You can turn that off.

Tracks: Period, fertile window, ovulation test results, discharge and many symptoms. Clue's help center lists BBT as something you can log in its tracking mode for people without periods. You can also log your birth control method. You can ask Clue for a copy of your data.

Best at: Research-backed reading and EU data storage.
Missing: No way to use it without an account, and Clue can read what's on its servers. Apple Health and Barkat lock synced data so the company can't.
Price: Free. Clue Plus is a subscription: $9.99 a month or $39.99 a year on the US App Store.

Sources: Clue privacy policy · Why do I need a Clue account? · How much does Clue Plus cost? · Clue on the App Store

04Natural Cycles

Price: $149/yr or $21.99/mo
Account needed: Yes
Where data lives: Natural Cycles' servers
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: IDs to ad partners
BBT and fluid: BBT
Birth control: FDA-cleared

Natural Cycles is the only app here sold as birth control. It is FDA-cleared in the US and CE-marked in Europe, and it reads your temperature from its NC° Band, a thermometer, Oura, WHOOP, some Garmin watches or Apple Watch Series 8 and later. It says it is 93% effective with typical use and 98% when used as intended. It's on iPhone and Android.

Privacy: You need an account and a subscription. Data is stored on its servers with encryption and pseudonymization; it doesn't describe end-to-end encryption. The policy says it never sells personal data in the usual sense, but under US state law definitions it may share identifiers, location from your IP address and web activity with advertising partners for targeted ads. It says it does not sell or share fertility, period, sexual activity or symptom data. It uses Google Analytics.

Its help center describes a Go Anonymous setting that separates your identity from your fertility data, with some limits on the app.

Best at: Birth control without hormones, backed by FDA clearance.
Missing: It's the most expensive app here, and it needs an account and a server copy. For tracking only, Barkat, drip and Apple Health keep more out of the company's hands.
Price: Subscription: $149 a year or $21.99 a month on the US App Store.

Sources: Natural Cycles privacy policy · NC° Secure · Help: I am concerned about my data being shared · Natural Cycles on the App Store

05Stardust

Price: Free; All Access subscription
Account needed: Yes
Where data lives: Stardust's servers
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: No sale; tracking IDs
BBT and fluid: BBT
Birth control: Not stated

Stardust pairs cycle tracking with the moon and astrology, which makes it the closest app here to Barkat in spirit. It's on iPhone and Android.

Privacy: You register an account, and Stardust collects your name, birthdate, email and phone number. It keeps login details with an outside service, SuperTokens, and ties your health data to a random ID instead of your contact details. It says it does not sell data and that it encrypts and anonymizes it. It doesn't describe end-to-end encryption. Its policy says it uses cookies and pixels for advertising and works with outside analytics providers, and its App Store label says purchases, identifiers and usage data may be used to track you.

Tracks: Period, ovulation forecasts, fertile window and BBT, logged by hand or from Apple Watch and Oura.

Best at: Moon and astrology features with health data kept apart from your name.
Missing: An account and ad tracking. Barkat offers moon phase and a birth chart with no account or trackers.
Price: Free. All Access is a subscription; the US App Store lists $6.99 a month and yearly plans from $24.99 to $39.99.

Sources: Stardust: Your Data · Stardust privacy policy · Stardust on the App Store

06Apple Health Cycle Tracking

Price: Free with iPhone
Account needed: Only for iCloud sync
Where data lives: iPhone; iCloud optional
Locked so the company can't read it: Yes, with two-factor
Sells or shares for ads: Apple can't read it
BBT and fluid: BBT
Birth control: No

Cycle Tracking is built into the Health app on iPhone and iPad and the Cycle Tracking app on Apple Watch. There's nothing to download.

Privacy: When your phone is locked with a passcode, Face ID or Touch ID, Health data is encrypted on the device. If you sync to iCloud with two-factor authentication on, Apple says Cycle Tracking data is end-to-end encrypted and Apple doesn't have the key. You can keep it on your phone by leaving Health sync off. Apps you connect to Health follow their own policies.

Tracks: Period predictions, fertile window, ovulation test results, BBT, spotting and symptoms. With Apple Watch Series 8 or later or any Ultra, wrist temperature can estimate when you likely ovulated, in some countries. Apple says Cycle Tracking should not be used as birth control.

Best at: End-to-end encrypted sync from a company you already trust with your phone.
Missing: Only works on Apple devices. Cervical fluid isn't mentioned on Apple's Cycle Tracking page, and there's no BBT chart with a coverline like Barkat, drip or Fertility Friend.
Price: Free with iPhone.

Sources: Apple: Track your period with Cycle Tracking

07Ovia

Price: Free
Account needed: Yes
Where data lives: Ovia's servers
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: No, since June 2025
BBT and fluid: Not stated
Birth control: Logs your method

Ovia, now part of Labcorp, covers cycles, trying to conceive, pregnancy and postpartum. Many people get it as a benefit through an employer or health plan. It's on iPhone and Android.

Privacy: You use it with an account, and data is hosted on Amazon Web Services and encrypted in transit and at rest. Ovia says that as of June 2025 it no longer shows ads to consumer users and does not sell or share personal data for advertising. Before then it shared identifiers and app activity with ad networks. If you get Ovia through an employer or insurer, some data may be shared with them; Ovia says to ask support for the details of your account. Consumer data is kept while your account is active and for seven years after.

Tracks: Period, fertility, symptoms, moods, sex and birth control. Ovia's pages we read don't describe BBT or cervical fluid charting.

Best at: Pregnancy and postpartum support, often free through a benefit.
Missing: Long data retention and possible employer or insurer sharing. Barkat and drip keep nothing on a server you can't control.
Price: Free.

Sources: Ovia privacy policy · Ovia on the App Store

08Premom

Price: Free; paid Premium
Account needed: Yes
Where data lives: Premom's servers
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: Marketing use; FTC 2023
BBT and fluid: BBT and LH tests
Birth control: Not stated

Premom, from Easy Healthcare (the Easy@Home brand), is built for trying to conceive. It reads photos of ovulation tests to estimate LH levels and syncs with its own smart thermometer. It's on iPhone and Android.

Privacy: You create an account, with email or a Google or Facebook login. Its policy says it may use personal information for marketing and advertising and may share it with providers for advertising and analytics. It uses the Braze SDK for personalized messages, with your consent for health data. We found no statement on selling data or end-to-end encryption.

In 2023 the FTC said Easy Healthcare shared users' health data with third parties, including two analytics companies based in China, and proposed an order that bans sharing health data for advertising. The company neither admitted nor denied the claims.

Tracks: Period, ovulation tests with LH readings, BBT charts and pregnancy. BBT can be exported to Apple Health.

Best at: Reading ovulation test strips.
Missing: A clear no-ads policy. Fertility Friend does detailed TTC charting with no ads or third-party analytics.
Price: Free. The US App Store lists Premium purchases from $12.99 to $37.99.

Sources: Premom privacy policy · Premom on the App Store · FTC: Premom proposed order (2023)

09Fertility Friend

Price: Free; VIP $45.99/yr
Account needed: Email
Where data lives: Servers in Canada
Locked so the company can't read it: No end-to-end claim
Sells or shares for ads: Neither
BBT and fluid: Both, plus OPKs
Birth control: Not stated

Fertility Friend has been around for years as a detailed BBT charting tool for people trying to conceive. It works on the web, iPhone and Android.

Privacy: It asks for an email address as your account ID but not your real name, address or precise location. It says it doesn't rely on data trading, shows no ads, uses no third-party analytics or marketing services, and doesn't share your data, anonymized or not. Data is stored on servers in Canada. A Restricted Account option permanently removes your email and keeps only your birth year. It doesn't describe end-to-end encryption.

Tracks: Period, BBT, cervical fluid, cervical position, OPKs and LH tests, symptoms and medications, with an automatic chart that marks your fertile window.

Best at: Detailed TTC charting from a company that doesn't sell ads.
Missing: Your chart lives on its servers in readable form. drip and Barkat do similar charting with no server copy the company can read.
Price: Free to start. VIP membership is $10.99 for 30 days, $21.99 for 90 days or $45.99 a year on the US App Store.

Sources: Fertility Friend privacy statement · Fertility Friend on the App Store

10drip

Price: Free
Account needed: No
Where data lives: Your phone only
Locked so the company can't read it: No server copy
Sells or shares for ads: Neither
BBT and fluid: Both
Birth control: Not stated

drip is a free, open-source cycle tracker from a volunteer collective at Heart of Code in Berlin. It's on iPhone and Android, including a direct download and F-Droid for people who avoid Google Play.

Privacy: drip says it collects no usage data or personal information, has no ads or tracking, and stores all data only on your device. Its App Store label says no data is collected. Your phone's own cloud backup may still copy it, so drip suggests checking those settings. Anyone can read the code on GitLab.

Tracks: Bleeding, BBT, cervical mucus or cervix, mood and more. Fertile days come from the symptothermal method, and drip shows them only once it has enough data. Period predictions start after three full cycles. You can export to CSV.

Best at: Open source, with nothing leaving your phone.
Missing: No sync between devices, so a lost phone without a backup means lost data. It skips cycles longer than 99 days, and it's English only. Barkat adds optional locked sync.
Price: Free.

Sources: drip home page · drip privacy policy · drip FAQ · drip source code

Questions

Which period tracker app is the most private?

Of the apps we checked, drip and Barkat keep the most out of the company's hands. drip stores everything on your phone and collects nothing. Barkat needs no account, has no trackers, and locks synced data so its server can't read it. Apple Health is a strong choice on iPhone if you turn on two-factor authentication.

Can a period tracker app share my data with the police?

A company can be ordered to hand over data it can read. If your data is only on your phone, or locked with a key only you hold, there's far less on the company's servers to hand over. Check whether an app offers end-to-end encryption or keeps no server copy.

Does Flo still share data with Facebook?

Flo's current policy says it does not share health data with third parties for marketing. With your consent, it shares device identifiers and app events with AppsFlyer, Firebase and TikTok Ad Manager. Its 2021 FTC settlement concerned earlier sharing with Facebook, Google and others.

Is there a period tracker that doesn't need an account?

Yes. Barkat and drip need no account or email. Apple Health needs an Apple Account only if you sync through iCloud. Flo has an Anonymous Mode that unlinks your name and email.

Which period tracker app works as birth control?

Natural Cycles is FDA-cleared as contraception. Flo and Apple say their apps are not birth control, and Barkat's predictions are only estimates.

Is Apple Health cycle tracking encrypted?

Yes. Health data is encrypted on a locked iPhone, and Apple says Cycle Tracking data synced to iCloud is end-to-end encrypted when two-factor authentication is on, so Apple can't read it.

Reading list

Open Barkat