The Privacy Risks of Period Tracker Apps: Is Your Data Safe?

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The Privacy Risks of Period Tracker Apps: A Brief Summary

Period tracking apps such as Clue, Flo, Glow, and others make it easy for women to track their menstrual cycles, ovulation, fertility, and overall health. But, these apps collect sensitive information about your personal health.

It’s important to know how these apps use this information and the entities they share it with, including how these third parties process your personal health data.

We looked at the privacy practices of the five best period tracking apps on both Apple’s App Store and the Google Play Store, namely:

  • Period Tracker Period Calendar
  • Flo Ovulation and Period Tracker
  • My Calendar
  • Clue Period and Cycle Tracker
  • Glow Ovulation and Period Tracker

We found that of these five, the Clue app offers better privacy than others. It gives you various privacy options and more control over your data (more details below!).

We also recommend using a VPN such as Surfshark to anonymize yourself when using period tracking apps so that they cannot see your real IP address or location information.

Read the full article below to learn exactly what kind of data the best menstrual tracker apps collect and share about you.

Period tracking apps are incredibly helpful in keeping track of menstrual cycles, fertility, and overall female reproductive health. But like many other technologies, they can pose serious privacy risks.

“Femtech” apps, as they are called collect highly personal information about your health and lifestyle. So, it’s vital to consider the privacy risks of menstrual cycle apps and know how these apps handle your data.

This is all the more important given the ongoing Roe v. Wade debate in the United States that affects women’s reproductive rights. Keep reading below to learn exactly what your menstrual cycle app knows about you and what it can do with your information.


Are Period Tracking Apps Safe?

In 2019, the UK-based charity Privacy International revealed how popular period and fertility tracker apps regularly shared user data with tech companies and marketers.

More recently, many individuals and organizations have raised concerns over how these apps can be legally obligated to disclose their users’ reproductive health data to governments or law enforcement. This raises the pressing question of whether the benefits of cycle tracking apps are worth the privacy risks involved.

The benefits of period tracker apps

On the plus side, menstruation and fertility apps make it easy to track and predict your menstrual cycle and find the best time to conceive by analyzing the menstrual data you add in. They do this by asking you to log the most intimate details about your health, information which you would probably not share with even your partner or closest friends.

Such details include things like the heaviness of your period, the color and odor of your vaginal discharge, the consistency of your poop, your sexual drive and activity, and a lot more.  The more data you provide, the more accurately the app can predict your menstrual cycle.

Using such an app regularly can help raise a red flag when something is “off” about your health. It can also be a treasure trove of information for your gynecologist if you routinely track your daily symptoms.

Period tracker apps and data collection

Unfortunately, the information gathered by period tracker apps can just as easily be misused when shared with third parties like advertisers and law enforcement. Unfortunately, many period tracking apps regularly share user data with third parties, especially free ones.

Moreover, even if period tracking apps delete your data upon request or never directly sell your data, their advertising partners may retain and pass on information to external data aggregators for profit.

In this way, the broader internet data economy makes it easy for anybody to purchase period tracking app data, which can then be traced back to you despite most apps claiming to only share “non personally identifiable” data. This is because things like your IP address, location, and device information are almost always tracked by period tracking apps and can be easily used to identify you.

Privacy policies show the dangers

So, in general, period tracking apps are not safe when it comes to protecting your privacy. However, this also depends on other factors like the privacy laws of where you live and which particular app you use.

That’s why we looked at the privacy policies of the five most popular period trackers to find out what kind of data they collect and what it’s used for. Many of these privacy policies and agreements carry serious privacy risks. The apps we’ve covered include the following:

  • Period Tracker Period Calendar
  • Flo Ovulation and Period Tracker
  • My Calendar
  • Clue Period and Cycle Tracker
  • Glow Ovulation and Period  Tracker

How the Five Best Period Tracker Apps Handle Your Data

There are tons of period and fertility trackers out there. We can’t discuss them all in one article so we’ve picked five of the most popular ones. Below, we’ve discussed the privacy concerns of the most popular menstrual cycle apps that have been downloaded by millions of users from the Google Play Store and Apple’s App Store.

For each app, we’ve looked at what data you must provide to use the app, what data you can keep track of, and how your data is used by the period trackers.

Note: If you use an iOS device, it’s easy to see what data an app collects about you as it’s mentioned on the app listing.


1. Period Tracker Period Calendar

My Calendar Period tracking app logoDespite the rather unimaginative name, this is the leading period tracking app on both the Play Store and the App Store. It has over 6 million ratings on the Play Store and over 100,000 on the App Store, with a score of 4.9 stars on both.

It is owned by Simple Design Ltd. and is based in the British Virgin Islands. However, on the App Store, the developer is listed as Abishkking Limited.

Also, there seem to be multiple versions of this app available under different names but with similar logos and interfaces.

Information you need to provide

When you open this menstrual cycle app for the first time, it asks you for some essential information you must provide to use the app. This includes the following:

  • The average length of your period each month. That is the number of days you usually bleed.
  • The average length of your menstrual cycle. In other words, the time between the start dates of two menstrual periods.
  • The start date of your last menstrual period.

Information you can track

After you have given this data, you will be taken to the app’s home screen. Here, you can see the expected date of your next period and your next fertile day (based on the app’s calculations).

Screenshot of Period Calendar period tracking app interface

At the bottom of the page, there are also different tabs, including Calendar, Log, Chart, Settings, and Add Note.

The Log section allows you to track various daily symptoms including the following:

  • How much blood are you losing today? There’s a 1-4 star rating that you can give depending upon the flow.
  • Have you taken a contraceptive pill?
  • Did you have sexual intercourse?
  • Do you have certain physical complaints, such as headaches and abdominal cramps?
  • What does your vaginal fluid look like?
  • Do you have mental problems, such as stress or fatigue?
  • Your mood
  • Your weight and temperature?
  • How much water did you drink today?

This is all optional information that you can choose to log or not log but the more data you provide, the better the app will be at “knowing” you and predicting your period or fertility.

What does Period Calendar Period Tracker do with your data?

This app is completely free to use and is supported by ads. That means it almost exclusively earns money from advertising as there is no premium version that users can sign up for.

The developer, Simple Design has a detailed privacy policy which you can access from the “Settings” section of the app. We checked it out and found that in addition to the data listed above, this app collects information about your devices, such as your IP address, location, and system data.

In addition, if you choose to sign in using a Google, Apple, or Facebook account, Simple Design may collect personal data already associated with that account.

They share all this data with affiliates and business partners. They also use your data for analytical and advertising purposes, Although it is explicitly mentioned that Simple Design does not sell your data, the company states that its partners may sell your data.

To protect your data, the app uses advanced encryption, both during transfers and storage. In addition, the app claims to conduct regular security scans. However, this is obviously not enough to guarantee complete security.

In the Settings menu, there is an option to “Delete all data,” but we are not sure if this actually removes all your personal data from the app’s servers, or simply from the app. In any case, once data is shared with third parties, they aren’t going to delete it.


2. Flo Ovulation and Period Tracker

Flo Period tracking app logoFlo is one of the most used menstrual cycle apps with over 2.5 million ratings on the Play Store and over 800,000 ratings on the App Store. It has a score of 4.6 and 4.8 out of 5 stars respectively.

In 2021, Flo was in the news for reaching a settlement with the US Federal Trade Commission (FTC) after sharing sensitive user data with third parties, most notably Facebook. We tested it and had a look at its current privacy policy to see how it claims to handle user data now.

Information you need to provide

When you first open the Flo app, it asks you to agree to its privacy policy, terms of use, and processing of your personal health data.

After that, it asks whether you are pregnant, trying to conceive, or just looking to track your menstrual cycle. Your answers are logged and serve as key data points.

Next, the app asks you to provide your age as this is a crucial aspect that affects menstrual cycles and fertility. Again, this may seem like harmless information, but when pooled together, it can provide key insights into your health.

After this, there is a short questionnaire that asks you several questions. This is optional and you can choose to skip providing this information if you want to.  Here’s what the optional questions look like:

  • Is your cycle regular?
  • What kind of menstrual symptoms do you experience (cramps, heavy bleeding, PMS, or mood swings)?
  • Do you have any reproductive health disorders (endometriosis or PCOS)?
  • Is there anything you want to improve about your sleep (difficulty falling asleep, waking up tired, or any other)?
  • Are there aspects of your mental health you’d like to address (anxiety, stress, mood fluctuations, or low energy)?
  • Is there anything you’d like to change about your b (low libido, painful sex, poor body image, or others)?
  • What is your fitness goal (weight loss, better nutrition, muscle growth, or any other)?
  • Is there anything you want to change about your skin (acne, blemishes, dryness)?

The app then creates a “personal program” for you based on your answers to the questions above. Lastly, it also asks:

  • If you take any supplements or medications
  • The start date of your last period

Information you can track

The home screen of the Flo app shows you how far ahead you’re on your menstrual cycle and your chances of getting pregnant if you were to have sex that day.

Screenshot of Flo period tracking app interface

You can tap the Log Period button to tell the app when you’re bleeding. Below that, there is the option to log other information, such as:

  • Your menstrual flow (if you’re on your period).
  • Your weight.
  • How much do you sleep daily? You can also give permission for the app to share data from another fitness app, such as Google Fit.
  • Your water consumption that day.
  • Your sexual activity and drive.
  • Your moods.
  • Physical symptoms like headaches, cramps, or fatigue.
  • Vaginal discharge or spotting.
  • Other factors like alcohol consumption, stress, diseases, injuries, or travel.

It’s not mandatory to provide all this data but the more you tell the app, the better it can work to make accurate predictions for you. You may also want to review the privacy settings of your fitness apps.

How does Flo share your data?

Flo states that by providing your data, you give the company the right to use this data for improving the app and for advertising purposes, such as displaying your content on the website.

In addition to the data you provide yourself, Flo collects information about your device, your IP address, location, and how you use the app. They use this data to make their menstrual app work (for example, to send notifications), to approach you, advertise, and comply with the legislation.

However, when it comes to advertising, Flo does not share any health-related information. In other words, only your technical identification data, age, subscription status, and use of the app are shared with AppsFlyer.

This is a SaaS marketing analytics platform that Flo uses to analyze your data. AppsFlyer shares this data with other partners, such as Google Ads and Facebook. Flo has explained this process with the help of a handy illustration in its privacy policy.

Screenshot of the Flo AppsFlyer

Flo can share all other data they have about you in an aggregated and anonymized manner with partners and research institutes. The company claims that this data can no longer be traced back to you.


3. My Calendar by SimpleInnovation

Simple Innovations Period tracking app logoMy Calendar is another female health app that has a rating of 4.9 stars on the Google Play Store and 4.8 on the App Store. It’s been downloaded by millions of users and is owned by SimpleInnovation LLC, though there’s little information about this developer.

Information you need to provide

When you open this app for the first time, you’ll need to provide the following information before you can start tracking your menstrual cycle:

  • Your name (optional)
  • What is your goal (Tracking your cycle, trying to conceive, or tracking your pregnancy)?
  • Your average cycle length or the length of your pregnancy
  • Your average period length
  • The start date of your last period

You can choose to answer “not sure” for any of these. So, in a way, this app requires lesser data than other menstrual apps before you can start using it.

Information you can track

On the home screen, you can see a calendar that shows you where you are in your menstrual cycle and when to expect your next period.

Screenshot of My Calendar period tracking app interface

You can click on the “+” sign to log your daily symptoms which include the following:

  • The severity of your period that day. You indicate this by ticking a number of drops (maximum four).
  • Your sexual activity
  • Your mental or physical symptoms like cramps, backache, bloating, or any other
  • Your moods
  • Whether you take contraceptive pills or not

You can also mention your temperature, weight, and any medication you are on, along with custom notes about the day. So, this app doubles up as a health journal of sorts.

What does My Calendar do with your data?

The SimpleInnovations privacy policy states that they “generally do not collect and store data from which they themselves can draw your identity,” but that they do have (other) information about you that, according to GDPR guidelines, is personal.

Therefore, when the company says it does not store your “personal data,” it is not explicitly clear which data they are referring to. In addition, the company shares your advertising ID and “non-personal data” with third parties. We approached the company for clarification about this and received the following response:

Your cycle information and notes are securely stored in Cloud servers and are used to predict your cycle and restore your data (if you create a backup account). The anonymized user data helps us to personalize and improve your use of the app. For this purpose, we share this data with others (such as Google Analytics).

We use your mobile identifiers (including Android Advertising ID, and Advertising Identifier for iOS) to personalize in-app advertisements [this means that all data from your phone, including the IP address, hardware, and software information, and other identifiable data are used. These are shared with third parties who provide these services.

This is similar to the privacy practices of other menstrual cycle apps we looked at. On the whole, your health data is shared with third parties but the company claims it is not personally identifiable to you.

Of course, there is no way to know for sure if this is really the case because there is always a chance of things like your location and device information being traced back to you.


4. Clue Period and Cycle Tracker

Clue Period tracking app logoClue was named the best free period tracking app in the Obstetrics and Gynecology Journal in 2016. Its been developed by the Berlin-based technology company BioWink GmbH.

Due to its location in Germany, it generally has better privacy practices than other free menstrual tracker apps.

Nonetheless, a report by Vice in May 2022 revealed how Clue’s user data was available on the data marketplace Narrative, from where anybody could easily purchase it.

This data consisted of a list of devices that have the Clue app installed, which in turn could be used to identify users if needed — an alarming privacy risk for sure!

Information you need to provide

When you first open Clue, it asks you for the following information:

  • Whether you’re tracking your period or your pregnancy
  • The start date of your last period
  • The average length of your menstrual cycle
  • Your birthdate
  • Your use of birth control

Unlike the period trackers covered above, you cannot use Clue without signing up. After you answer the initial questions listed above, you will be asked to sign up with your email address or sign in using a Google, Facebook, or Apple account to start using the app.

Information you can track

The home screen of the Clue period tracking app shows your menstrual cycle and indicates the expected start date of your next period.

Screenshot of Clue period tracking app interface

The Calendar tab allows you to view an overview of your past cycles and look three months ahead. The app allows you to keep a daily log of the following data:

  • The intensity of your period (light, medium, heavy)
  • Your moods, such as happy, quick-tempered, sad, or PMS
  • Any pain you experience, such as cramps, headaches, ovulation pain, or breast tenderness
  • Your weight
  • Your temperature
  • Your average sleep time
  • Your energy level
  • How your skin feels, such as dry, oily, acne-prone, or normal
  • How your hair feels, such as good, bad, greasy, or dry
  • Your bowel movements, such as diarrhea or constipation
  • Your focus and stress level
  • How motivated you are
  • How social you are that day
  • Your cravings for carbs or sugar that day
  • Your exercise and activity for the day
  • The texture of your vaginal fluid
  • Whether you have had (un)safe sex and how high your libido is
  • Your method of contraception

Clue also offers helpful health tips personalized to you. For example, with every answer you give, Clue provides information about how it is related to your cycle and what is normal.

It is also an app that does not focus on women, but on everyone who has a uterus. For example. the information section has a separate LGBTQIA+ section, which, among other things, talks about the effect of hormone treatments on trans men.

What does Clue do with your data?

Clue collects data about your phone, your IP address, location, and what you do within the app. They also collect the data that you track in the app. They only share this sensitive data in an anonymous way — in the form of large datasets — for academic and clinical studies.

They share the remaining data with different marketing analytics companies, including Braze, Firebase, Sentry, and Adjust. The first three companies help Clue to improve the app while Adjust is used for advertising campaigns.

Fortunately, Clue gives you the option to refuse tracking and data sharing with Adjust. You can find this under Privacy Settings in the Settings menu of the app.

Further, Clue’s privacy statement states that your profile data is stored separately from your period tracking data. Moreover, if you use a password, it is stored with single-sided encryption, so that employees cannot access it.

Clue also shares helpful information on its website about how they use your data and what users can do to protect themselves.


5. Glow Ovulation and Period Tracker

Glow Period tracking app logoCalifornia-based Glow Inc. has an ecosystem of four health apps that includes Eve, Glow, Glow Nurture, and Glow Baby. Of these, Glow is the most popular and is used to track fertility and the menstrual cycle.

In 2016, Consumer Reports found a security breach in Glow that could let almost anyone with a user’s email address access all the health data they tracked.

In 2020, the state of California reached a settlement with the company that included a $250,000 fine and a number of provisions to ensure that Glow protects the privacy and security of its users. Glow’s data privacy is still a concern, we believe.

Information you need to provide

  • Are you trying to conceive right now?
  • Your name
  • Email address and password to create an account
  • Your birth date
  • Your method of birth control
  • Your average cycle length
  • The exact or approximate start date of your last period

You must agree to their terms of use and privacy policy before you can start using the app, though this is standard practice.

Information you can track

The home screen of the Glow app shows the predicted day of your menstrual cycle and links to articles related to female health.

Screenshot of Glow period tracking app interface

You can click the “+” sign to log daily symptoms which include the following:

  • Your menstrual blood flow if you’re on your period
  • Your sexual activity that day
  • The appearance and amount of your cervical mucus
  • Physical symptoms like acne, bloating, backache, constipation, or others
  • Stress levels and moods
  • Sleep duration
  • Your basal body temperature

You can also add extra information in the form of notes.

What does Glow do with your data?

By default, your profile information on Glow, including your name, profile URL, and any location or profile photo that you choose to add — will be visible to other app users.

You can choose to make your profile private from your account settings. This makes the app somewhat similar to social media apps and anything you choose to “post” in the Community section of the app is visible to anybody unless you hide it from your account settings.

Glow’s privacy policy states that the company can share health data collected on its app with third parties. These include affiliates, advertising partners, other service providers, and professional advisors, such as lawyers, auditors, bankers, and insurers.

If necessary, it can also share data with law enforcement agencies or governmental agencies. Data can be used to operate and maintain the app and to inform users about products and services that may interest them.

This means that Glow can use user information to deliver “targeted marketing.”  In other words, even though the data is not sold, it’s an integral part of the company’s business model.

In fact, you can’t delete your account directly, even when you completely stop using the app. You need to email the company if you want them to delete your information or your account.


How to Stop Menstrual Apps from Tracking Your Data

Just like other health apps or fitness trackers, period tracking apps come with some privacy risks. But they also make it easy and convenient to know your body better and keep track of your cycles, fertility, and overall health. After all, that’s why millions of women use these apps every day.

Fortunately, there are a couple of steps you can take to stay more anonymous when using a period app, which will make it harder for third parties like marketing analytics companies to gather and use your data.

Firstly, to stop seeing personalized ads, do the following on your smartphone:

For Android devices

Go to Settings > Privacy > Advertisements and privacy > and turn off Personalised ads. Then, go to Advertisements and privacy and tap on “More information” to also turn off the personalized advertisements there. Finally, in your settings, go to Privacy > Ads > Opt-out of ad personalization.

For iOS devices

On iOS, go to Settings > Privacy > Tracking > and turn off the Allow apps to request to track button. You can also change this setting for individual apps in the Tracking menu.

Secondly, if you want to remain completely anonymous, it’s best to install a VPN on your phone. This will prevent your cycle tracker and other apps from knowing your real IP address and location.

This helps prevent your data from being traced back to you. We recommend using NordVPN or Surfshark as they both offer a foolproof way to stay completely anonymous while offering many other benefits. You may want to review the best VPNs for Android or the best VPNs for iPhone too.


The Bottom Line

Taking such steps to protect your privacy gives you a bit more control over your personal data. But there’s no denying that greater measures are needed too. Tracking menstrual cycles can reveal a host of valuable health information for individuals, health care services, scientists, and researchers.

Companies need to work harder to introduce greater privacy controls to protect an individual’s privacy and to ensure they handle such sensitive data carefully. Data security audits, for instance, may instill confidence among users.

Privacy Risks of Period Tracking Apps: Frequently Asked Questions

Got a question about the privacy concerns of your period tracking app? We’ve got you covered in our FAQ section below. Just click a question to see the answer.

Period tracking apps collect extremely personal health information about you, which can pose serious privacy risks. It’s crucial that this stays private but most of these apps have a business model wherein they share this information with third parties like advertisers or other agencies.

Most of the popular period apps do not directly sell your data. But they share your data with advertisers and other third parties, which can lead to serious privacy risks.

For instance, in May 2022, data from the Clue period tracker app was found for sale on the data marketplace Narrative even though Clue is one of the most trusted period tracking apps to use.

The Flo app, just like other period trackers, shares your data with third parties including advertisers and marketers. In 2021, Flo was in the news for reaching a settlement with the US Federal Trade Commission (FTC) after sharing sensitive user data with third parties.

But even after this, its privacy policy and terms of use still allow for extensive data sharing.

Your period app collects extremely personal information about your health that you probably don’t share with anyone else. Ideally, this data should be kept private but it’s not a good idea to blindly trust your app because these apps generally share user information with other parties.

We recommend you use a good VPN such as Surfshark to anonymize yourself and prevent your data from being traced back to you.

The Clue app is one of the most trusted period tracking apps because it has a solid privacy policy and lets you opt out of tracking and sharing your data. It does not sell your data but the third parties it shares data with for business purposes may sell your data.

However, there are some serious privacy risks of using period tracking apps that you should know about.

Tech journalist
Mehak has been writing for over a decade and is passionate about helping people have safer, healthier relationships with all things tech. She has a master’s degree in communication and is especially interested in the impact of technology and the internet on global communities.