Flo Health was founded in 2015 by Dmitry Gurski in Minsk, Belarus. The founding insight was not about privacy — it was about comprehensiveness. Existing period tracking apps were thin: they tracked cycles and predicted ovulation. Flo was built to be a full health companion, covering pregnancy tracking, ovulation prediction, symptom logging, health insights, and eventually AI-powered health analysis. The combination of breadth and accuracy in health predictions drove initial growth to tens of millions of users by 2019.
The privacy inflection point came from an unexpected direction. In 2021, the US Federal Trade Commission took enforcement action against a period tracking app competitor for sharing users' fertility data with Facebook and Google without clear consent. The case made international news. Women who had been casually logging their periods in apps suddenly understood that their most intimate health data was being sold to advertisers. Flo, which had already been building a privacy-focused model, found itself in a position to make an explicit commitment: Anonymous Mode, a feature that let users track their cycles without any account or identifying information.
The 2022 US Supreme Court decision overturning Roe v. Wade intensified the stakes dramatically. In states that criminalised abortion, period tracking data suddenly had potential legal consequences. Law enforcement requests, civil litigation, and corporate data sharing agreements all became potential exposure vectors for women using apps that retained their health data. Flo's Anonymous Mode became one of the most-discussed privacy features in consumer health tech. The conversation extended Flo's reach into demographics and geographies that had not previously considered it.