I am very excited about the first edition of Growth Case Studies. Flo is the first company we’ll be studying in this series. I picked Flo as the first case study for the following reasons:

1. A lot of people asked for it.

   

2. It’s a truly unique company and no other product in its category comes close. Women’s health features are often add-ons to health apps and none of them come close to Flo in terms of capabilities, user milestones, and revenue numbers.

For each company I cover in this series, I will delve into its founding narrative, product concept, revenue model, acquisition journey, product strategy, retention model, achievements, critiques, and future outlook. I couldn’t have done this without a wonderful team of volunteer researchers. Ayomide Ogunsiakan, Toluwani Daniel, Yusuf Olatoye, Esohe Obaseki and William Abrefa. I refer to this team and myself when I use ‘We’ in this series.

So let’s get to it! Feel free to jump to any section in this case study.

• What is Flo?

• Origin Story - How was Flo founded?

• Flo - Product and Thesis

  • Flo Onboarding

  • Flo Time to Value

  • Understanding Flo’s user retention loop

  • Flo - Product Strategy - A super app for women

  • Evolution of the Flo app and launch strategy

• Flo - Business Model and Monetisation

• Flo - Competitive Landscape

• Acquisition - How Flo gets new users

• Revenue and Success

• Fundraising and Valuation

• Drawbacks and criticisms

• Flo’s Future

What is Flo?

Flo is an all-in-one application for women's health and hormone tracking. It helps women track their period, predicts fertility windows, and even offers pregnancy and early motherhood info. Women can log symptoms, moods, and activities to see how their cycle affects them. It's like a personalized health calendar for everything going on in their bodies.

Flo uses data and predictive machine learning to learn cycle patterns and predict women’s next period. In addition to this, it has a team of health experts to provide reliable information to improve women’s health.

Flo - Origin Story - How was Flo Founded?

Flo was founded in 2015 by Belarusian twin brothers Dmitry and Yuri Gurski. Both brothers began working together at 16, launching an educational book publishing company Ideanomix, and another women’s health app Only Women - which eventually shut down. Ideanomix is still an active publisher with over 1500 books in its catalogue.

Yuri Gurski graduated from Belarusian State University with a master's degree in journalism and bagged an Executive MBA in 2010 from the Kozminski University program at the IPM Business School in Warsaw, Poland. Dmitry Gurski on the other hand had his first degree in Pharmaceutics and Drug design from Belarusians University, MBA from Kozminski University, and eventually bagged an Executive MBA from Stanford University in 2019.

Dmitry and Yuri launched the Flo app 11 years after Only Women, having figured out a better way to build a user-friendly, health-tech solution for women. The brothers infused their learnings from publishing, technology, and healthcare into Flo. They were early on artificial intelligence and machine learning as tools to drive behavioural change for people who cared about their health.

Flo’s founders are complementary. Dmitry had spent many years publishing content on the internet as a freelancer. Combined with his brother, Yuri’s ability to build tech products, the two are a digital development and distribution powerhouse. In the coming sections, we will study how Flo creates content that drives tens of millions of visits monthly.

Flo’s Product and Thesis

Flo’s raison d’être is simple. It’s an app that uses predictive technology and artificial intelligence to help women measure and improve their reproductive health. The app provides personalized Period Tracking and Cycle Predictions, Health Assistant, Health Insights, Community, and Health Reports. Flo supports women throughout their entire sexual and reproductive journey. In this section, we will thoroughly break down the Flo product.

Flo Onboarding

Flo is likely one of the most personalized apps available. It begins by asking users a few questions to collect relevant data (including height, weight, and year of birth) and immediately provides valuable utilities for women who use it. Here’s a walkthrough of its onboarding screen.

After collecting this data, Flo uses it to predict specific events in a woman's hormonal cycle with reasonable accuracy. The app then suggests actions based on the user's goals. Unlike most apps that require signup upfront, Flo encourages users to save their progress by signing up at the end of the data collection process.

Time to Value - How do Flo’s users get value? How long does it take to get value?

Software products must get time to value right. Flo’s users get value immediately after they log their periods to make accurate predictions. However, long-term users are more likely to gain improved knowledge about pregnancy and their menstrual cycle. 

Flo empowers women to understand their bodies' language, equipping them with the knowledge to manage their overall health and well-being proactively. The app provides users with near-accurate cycle predictions, insights, and a wealth of science-backed, user-friendly content. It also helps women achieve their goals: to understand their bodies better, adjust their lifestyle, get pregnant, or keep from getting pregnant.

In addition, the communities on the app provide a safe space for women to share their struggles and speak on ‘taboo’ topics which allow them to make informed decisions regarding their sexual and reproductive health.

So far, its been successful at delivering value. Flo’s users become more knowledgeable about their menstrual cycle (89.0%) and pregnancy (84.6%) within 30 days of use according to a 2022 study carried out by the company in conjunction with a researcher at the University of London and Technische Universitaet Berlin.

Flo - Retention Loop

Retention is key for apps - key signals for success are the period within which a user is expected to return and a solid retention rate. There are key components to Flo’s retention loop - this keeps its users returning to the app.

1. Personalized User Data
   
   Flo has built a loop that is self-sustaining for each user. The more a woman uses Flo, the more it can accurately guide her and the more value it provides to her.

   Because Flo requires women to log their periods, tick off accuracy times, and enter events like sex or how they feel, retention is immediately baked into its model. Each time a user corrects period dates on Flo, adds that they’ve had sex, or logs their feelings, they send data to Flo’s decision engines, which personalizes the service. The only way to get the best value from Flo is to use it. The service has created the perfect loop of usage for its customers.

2. Notifications
   
   Flo’s notifications are central to the user experience. The company has built several notification and email flows by segmenting millions of users and nudging them to take appropriate action. These notifications help Flo users remember to do certain things like logging their period, updating their profile, or explaining why they might be feeling a certain way. The notifications are quirky, helping the company to deliver its brand to users

   

   Based on user actions or behavior, the company has launched an infinite loop of push notifications (with a rate limit) which could be turned off at any point.

   

   
   According to Ivan Zhamoidzin, a software engineer at Flo, The notification loop is based on two major settings: scheduling horizon and ping interval.

   The scheduling horizon describes how many days ahead we pick and schedule reengagement notifications.

   Ping interval controls how often we emit a dummy user profile update for stale users and the pace of newly published notifications.
   

3. Content - Flo Stories
   
   In addition to these tickers and activities, Flo has included media content in a story format similar to Whatsapp Status, Instagram Story, and Snapchat. With this feature, Flo creates daily content to help women better understand their bodies.
   

   In an interview with The Drum, Annie O’Leary, the Chief Editor at Flo, says the company created content for pregnant women based on search engine insights on questions women ask throughout their pregnancy cycle. It then tested the feature by rolling it out to 30,000 users and saw incredible results. For freemium users, it saw a 30%+ increase in app opens. The content was designed in multiple different formats and the format with the highest engagement was then deployed to over 480,000+ pregnant women with a 61.42% watch rate and 0.75% of user trials after watching.
   

4. Flo Secret Chats

   

   
   Flo developed secret chats as a place for women to anonymously discuss several topics and receive responses from other women worldwide. The app is the perfect place for women to learn from other’s experiences and share their own experiences. Each chat is categorized by topic and users can filter between Top, Newest, My, and Expert. Secret Chats is also algorithmically powered and delivers content to women based on their age and goals. Flo ensures this chat section is actively pre-moderated - this creates a filter for chats, and their responses and protects women from harassment or bullying.

5. Flo with Partners

   

   
   Flo has built a brilliant feature that allows women to share their cycles with their partners. This has extended Flo’s usage beyond women and now includes men (who would typically not use such apps) in the conversation about women’s cycles. This feature includes data about a user’s partner’s cycle, how their partner might feel, and even tips to make their partner feel better. It also holds loads of text and video content under its insights sub-feature. These insights deeply explain topics and issues around a woman’s period including topics like What is a period and What affects sex drive?
   
   For couples trying to conceive a baby, this makes Flo the essential companion in the reproductive process. 

Flo - Product Strategy - A super app for women

Flo’s CEO Dmitry Gurski considers Flo - a super app for women. The company started as a period or cycle tracker and has added features to keep growing in the women’s health sector.

In an interview with Unicorns Lithuania, Dmitry says, 

On competition, Dmitry also added

Women’s health (and beauty) is a largely unexplored sector for application developers and venture capitalists. Because most of these people are men (only around 2% of startup founders and 15% of co-founders are women), they are completely oblivious and have largely ignored this sector. This has led to less competition for apps focused on women or promoted towards women’s needs. Inadvertently, the market is wide open for apps that work, improve women’s health, and deliver value. Many technology sector analysts and industries forget some simple facts - Women are the economic engine of the internet - responsible for 82% of fashion ecommerce shopping, and over 78% of Amazon Prime Day purchases.

Evolution of the Flo app and Product Launch Strategy

This section will discuss Flo’s product strategy and core thesis, how it creates hypotheses that build new features, and its testing methodology.

Flo 0: An application to track periods and view future cycles, sending daily notifications to users about the symptoms they could experience.
Flo Today: A super-health app for women to track everything about their body and how it impacts their lives.

This super-health-app for women thesis drives everything at Flo and informs how it decides what new features to build for its over 300 million user base. 

The company builds and tests features by creating a hypothesis, defining a user segment to test the hypothesis, and then defining metrics to benchmark against. In this blog post, Flo CEO, Dmitry explains Flo’s thinking and highlights that tests don’t always show immediate impact. We can infer that Flo runs A/B tests for new features or changes and unlike most companies, focuses on how these changes impact long-term revenue instead of short-term impacts. 

In the same post, he explains that the company's OKRs drive the metrics it benchmarks and then selects multiple levels of product metrics that impact the overarching OKRs. To improve these lower-level metrics, hypotheses are brought to the forefront, designed in Figma or Miro, and then built to be tested. 

The image below shows how Flo’s product team thinks about the impact of the features they build. 

In the image, we can see how Notifications directly impact opened cards and impressions but also indirectly impact the number of active days per user and lengthen the retention curve. We can also see how daily content, the knowledge base, and content quality impact the same retention curve metric. The Flo team recognizes that there’s hardly one thing that affects retention and the ‘problem’ can be tackled on multiple fronts. 

Flo is an app that gives users data-driven results and its product decisions are heavily data-driven. You can read deeper into Flo’s experimentation strategy from the CEO, Quantitative User Researcher, and, Data Platform Product Owner.

Flo - Business Model and Monetisation

How does the company make money? Flo is one of the millions of apps that employ the freemium model: while it is free for all users, it also offers added features for paid subscribers. These features include a daily well-being plan, video courses and content, and unlimited access to Flo’s health assistant, a chatbot designed to answer questions and improve understanding of menstrual health.

Flo’s pricing pushes users to opt for the optimal annual option as a price-sensitive lock-in. The difference between $15 and $40 is just $25 - a significant discount compared to a monthly payment of up to $180 annually.

We also found some add-ons and plans like the Flo Pregnancy Tracker, Flo Birth Control Reminder, and Fertility Tracker Premium. Flo doesn’t list its pricing on its website (only in the app) which suggests that Flo uses dynamic and probably location-based pricing depending on each user’s location. This pricing strategy isn’t uncommon; many global services adjust pricing based on the user’s affordability.

Here’s a breakdown of the differences between Flo Free and Flo Premium.

By 2024, Flo Premium had over 16 million users and opened up its Pass it On program to 1 billion women - this means women in participating countries have free access to Flo Premium. More on this below.

Flo - Competitive Landscape

Flo isn’t without competition. It's surrounded by a bevy of services like Grace Health, Glow, Noula, Clue, and, Aavia. Clue and Noula primarily target women looking to track their fertility cycle and birthing parents. Grace Health on the other hand extends its services to general health and wellness. Glow also goes beyond tracking and offers deeper support for women undergoing fertility treatments, including IVF and IUI, connecting them with fertility experts. Noula shut down in May this year.

Flo also competes with generalized health apps like Google Fit, Apple Health, Mi Fit, Zepp Life, Fitbit, and Samsung Health, providing cycle tracking for women. These services integrate directly with smartwatches and other health trackers, picking up on data like heart rate, sleep quality, and fitness activity. The table below compares Flo with indirect competitors.

Acquisition - How does Flo get new users to discover its product?

According to website traffic platform Similarweb, Flo gets a huge chunk of website traffic from Search Engines, followed by direct visits to its website and, social media. Currently, it doesn’t seem to run many ads, so as a traffic driver, those come in a distant fourth. Fifth is referrals from other websites such as women’s health and generalist websites.

The Flo website sees about 6 million visitors each month driven by its content efforts on the Flo Health Library. The library is a massive content repository for women’s health and includes all topics from puberty to motherhood and menopause. The purpose of these articles is to drive search engine traffic to the website. There are over 100 articles within the library and it’s updated weekly. 

In addition to these articles, Flo backs up its SEO sauce with free calculators. These are simple free tools on the web that help women calculate certain dates. Its website has about 9 calculators which are all free.

When you build a great product, people talk about it. Flo isn’t different. Its largest acquisition source is Word of Mouth

Flo’s largest driver of traffic is word of mouth. Every woman I talked to for this case study said they learned about Flo through a friend, cousin, or sister or saw a post about it on social media. The app is so valuable that women talk about it naturally. We found that of all referral traffic, Flo gets the most traffic from Whatsapp, the largest chat app in the world. This is consistent with apps that grow via word of mouth. Friends and family share them in messaging apps.

While Flo currently doesn’t run large ad campaigns, here are some campaigns in the company’s history.

Let’s Talk About It. Period

In this video series, supermodel Natalia Vodanovia interviewed celebrities like Emily Ratajkowski, Maria Borges, and Soo Joo Park. The series talks about womanhood, their expectations of being a woman compared to their experiences, and how their periods change their lives. This campaign generated over 250K views on YouTube and was promoted on other social platforms.

Flo-for-Business Referral Campaign

Second is Flo’s Business Campaign. We found the Flo-for-Business Referral Campaign which enabled businesses, their human resources department or other department to offer One year of Flo Premium to all their employees. Flo took this seriously and assessed each business by hosting meetings with the business representatives. This campaign launched in February 2022 and has now shut down.

Flo Pass it On

This is the company’s largest and most impactful campaign to date. In October 2022, Flo’s Pass It On started by giving women in 22 countries free & unlimited access to Flo Premium. In November 2023, just after the anniversary of this project, the app added 66 countries to this list. According to an announcement blog post, this opens up Flo Premium to 1 billion women worldwide who can access the service for free - including women in some of the largest countries in the world like India, Indonesia, and Nigeria. At the time of release, over 10 million women worldwide used Flo Premium. There’s just one caveat: the program is available to Android users only. Flo’s assumption here is interesting - because iPhones cost far more money than the average Android in these countries, the company assumes iPhone users are richer and can afford to subscribe to Flo. 

Flo - Revenue and Success

This case study wouldn’t be complete without talking about money. Flo is one of the most successful stand-alone apps in the world. This year, its CEO Dmitry Gurski, said it had 70 million monthly active users. In the health and fitness category, Flo is the biggest app. Period.

Flo’s 2023 Annual Recurring Revenue was $192 million (40% annual increase) and since 2018, Flo has maintained the lead as the largest global health app by downloads and active users.

In August 2024, Flo’s CEO announced 5 million paying subscribers, an increase of over 55% year-on-year. We couldn’t find revenue for all of Flo’s existence but with a total of $429M in estimated revenue in the last 3 years, Flo has earned over 5.72x on its pre-2024 capital raises.

Flo Health Inc - Fundraising and Valuation

The company is on a path to mega-app success and investors are in line. Flo has raised $275.5M in funding so far and at its last round in July 2024, it became a unicorn. Its backers include General Atlantic, Target Global, VNV Global, and Flint Capital. Here’s a breakdown of Flo’s fundraising history.

Flo - Drawbacks and Criticisms

Flo’s success is not without its drawbacks. In 2019, the Washington Post published an investigative piece about Flo’s data-sharing practices with third parties. Like many digital products and apps, Flo shared user data with platforms like Meta and Google. This data is used to retarget website visitors and users who might drop off from certain processes, and enable ad targeting via Meta’s ‘Lookalike audience’ feature. The company did this largely without user consent and was fined by the United States Federal Trade Commission in 2021.

This fine led to an unknown number of women deleting the Flo app as a response to Flo’s privacy violations. Many users were shocked that their private sexual and reproductive activity was being shared with advertisers and advertising platforms.

Flo responded to this and built features like Anonymous mode and Security sharing. These features have brought the company privacy awards. It has also open-sourced its technology for this feature and received ISO certifications for its work to improve privacy. 

Flo - The Future

Flo’s future is bright. It’s a freemium service that’s achieved high paid user retention numbers in a unique category with low competition. Its product and retention model also encourage consistent usage - the more you use Flo, the less you’re likely to move to another app. The cost of switching from Flo to another app is too high. Many women I spoke to have used Flo since their teens and couldn’t imagine life without it. 

Unlike many freemium apps, it’s figured out a way to earn good revenue via premium subscriptions, and add-ons and continues to grow this pie. 

In a recent interview with TechCrunch, here’s what the CEO Dmitry says:

Here are some possible future scenarios for Flo:

1. Acquisition
   
   A healthcare service provider could acquire Flo. Large medical providers would love to get their hands on Flo’s data - for research and customer purposes. Women’s health has been largely ignored and more funding is moving into the sector.
   

2. IPO

   Flo could go public and begin trading on a global stock exchange. It trades at a fair value compared to revenue and makes more profit and consistent revenue than most tech companies that have gone public in the last 5 years. 
   

3. Remain private and build 

   
   Flo earns enough revenue and profit to provide consistent dividends to its shareholders. It’s crafted a niche in the women’s healthcare category and can continue to build, test, and deploy features that improve women’s health.

Conclusion

Flo's innovative approach to women's health demonstrates the power of depth. A product like Flo competes with native apps from some of the world’s biggest tech companies. Still, by leveraging data, personalisation and useful features, Flo has created a unique app that empowers women to understand and manage their bodies, ultimately improving their overall well-being. The company shows us that there’s an opportunity to build profitable, sustainable and great products in niches that are ignored and underserved.

Thank you for making it to the end of this case study. I hope it was useful to you as it was a learning experience for me. If you learnt much, please share this with friends, colleagues, managers and family.

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