Most people in tech have heard the word “FemTech.” Fewer know that Ida Tin invented it. The Danish entrepreneur co-founded Clue in 2012, coined the term “FemTech” in 2016, and spent over a decade building one of the most trusted health apps in the world. Her work sits at the intersection of data, reproductive health, and technology, and it continues to shape how the industry thinks about women’s bodies.
Clue now has 10 million monthly active users across 190 countries, with over 100 million total app downloads and 1 million paid subscribers. It tracks periods, fertility windows, pregnancy, and perimenopause, all grounded in science and built with a strong privacy policy under German and EU data law.
The Idea Behind Clue:
Tin was motivated by a straightforward frustration. She found it difficult to get basic, reliable information about her own reproductive health, things like when her fertile window was, or what side effects different contraceptives might have. She saw that as a product gap and a systemic one.
She co-founded Clue in Berlin in 2012 alongside Hans Raffauf. The app launched in 2013 and grew quickly. By November 2015, the active user base had risen to 2 million across more than 180 countries. That same year, Tin worked with Apple to help develop period tracking for their HealthKit platform, an early signal of how mainstream the category was becoming.
Naming an Entire Sector:
In 2016, Tin put a name to the category she was helping build. She coined the term “FemTech” to describe technology addressing the needs that people with female biology have, initially focused on reproductive health, and later expanded to include areas like brain health and bone health where women are disproportionately affected.
The label stuck. It gave investors, founders, and media a shared vocabulary. The FemTech sector is now projected to exceed a trillion dollars by 2040. Tin’s terminology helped catalyze that attention toward a historically underfunded space.
Research and Data Contributions:
Clue’s contribution to women’s health research is one of its less visible but significant impacts. Under Tin’s leadership, the app supplied anonymized user data to research studies in collaboration with institutions such as the University of Exeter, covering conditions like endometriosis and premenstrual dysphoric disorder (PMDD).
Clue has also partnered with Oxford, Berkeley, MIT, and other leading institutions to advance women’s health research using real-world cycle data. For a category that has historically been under-researched, this represents a meaningful structural contribution.
A Leadership Transition:
In 2021, Clue became one of the first apps in the United States to receive FDA clearance as a certified digital contraceptive. That regulatory approval validated years of algorithm development and positioned Clue as a serious health tool, not just a wellness product.
Tin stepped down as CEO that same year and moved into the Chairwoman role. She is now founding FemTech Assembly, a think tank focused on connecting women’s health investment to economic growth and sustainability. She is also writing a book on the birth and rise of FemTech.
Beyond the App:
Tin’s background before Clue included co-founding a motorcycle touring company with her father, traveling through Vietnam, Cuba, Chile, and Mongolia, and writing a memoir, “Direktøs,” that became a Danish bestseller.
She speaks regularly at events including the World Economic Forum and South Summit, and has been featured in The New York Times, Forbes, and Der Spiegel. Her reach across health, tech, and policy circles makes her one of the more connected voices in European tech.
Building Beyond Clue:
Ida Tin did not just build a product. She named a market, helped legitimize it with institutional research, and is now working to connect it to broader economic and health conversations. That progression, from app founder to sector-shaping voice, is what makes her work relevant to anyone tracking the future of HealthTech and women’s leadership in European startups.
