500M+ downloads. 77M+ monthly users. A decade of building – and we're still accelerating.
Flo is the world's #1 health & fitness app worldwide on a mission to build a better future for female health. Backed by a $200M investment led by General Atlantic, we became the first product of our kind to reach a $1B valuation in 2024 – and we're not slowing down.
With 6M paid subscribers and the highest-rated experience in the App Store's health category, we've spent 10 years earning trust at scale. Now, we're building the next generation of digital health – AI-powered, privacy-first, clinically backed – to help our users know their body better.
The job
We are now building the next generation of AI-powered, privacy-first, clinically backed digital health solutions. Scientific integrity is the foundation of our work, engaging over 100 thought leaders and establishing research partnerships with institutions like Stanford, Yale, John Hopkins and more.
The Role: Setting the gold standard for software as a medical device
We are seeking a highly skilled Senior Research Scientist to join our Science team for 20-30 hours per week. This role is centered on working with big data to answer research questions within Women's Health to write a first-author paper for a top-tier journal. You will also be supporting the successful execution of our clinical investigation into the safety and effectiveness of our new medical device, and the scientific strategy and planning for future devices. The mission impossible of your job is to bridge the gap between "interesting research", "clinical proof", "regulatory requirements", and "business metrics".
You will work closely with the Lead Research Scientist and the Director of Science, but your impact of research will be felt through the whole company, across the legal, compliance, and product teams.
**What you'll be doing
You'll be responsible for:**
- Provide day-to-day scientific input and oversight for ongoing clinical studies. This involves data analysis, manuscript writing, and ensuring protocol adherence across teams.
- Assemble high-quality regulatory documents (including study protocols, statistical analysis plans, study reports) for submission to the FDA and notified bodies (EU MDR).
- Prepare, extract, and analyze large-scale datasets, performing statistical analysis and developing reporting specifications (SAPs, sample size estimation).
- Write research papers for publication in peer-reviewed scientific journals.
- Directly contribute to Flo's scientific strategy by designing and planning future medical device studiesand advising on global regulatory compliance requirements for new products.
Must Have:
- PhD or Postdoc in Public Health, Reproductive Medicine, Population Health, Biostatistics, or other related fields.
- Direct experience of leading the design, execution, and data analysis of clinical research studies.
- Experience preparing documentation and supporting trials subject to FDA, EU MDR*,* or other global regulatory compliance bodies (Class II or higher).
- Strong working experience with data analysis and statistics (e.g. survival/lifetable analysis, linear and logistic regression, mixed models, etc.) in Python or/and R, including strong proficiency in writing complex SQL-queries.
- Strong publication record in peer-reviewed journals (as a first-author) and proven ability to write rigorous study protocols, statistical analysis plans, and scientific reports.
Nice to Have:
- Working experience in projects related to Software as Medical Device (SaMD).
- Prior experience applying predictive models such as decision tree algorithms (e.g., CatBoost) or Bayesian networks.
- Experience of conducting systematic reviews and meta-analyses.
- You are meticulous but fast. We are a high-growth tech company. We need someone who can maintain academic-level precision at the speed of a scale-up.
#LI-VT2
How we work
We're a mission-led, product-driven team. We move fast, stay focused and take ownership – from brief to build to impact. Debate is encouraged. Decisions are shared. We care about craft, ship with purpose, and always raise the bar.
You'll be working with people who take their work seriously, not themselves. It takes commitment, resilience, and the drive to keep going when things get tough. Because better health outcomes are worth it.
What you'll get
We support impact with meaningful reward. Here's what that looks like:
- Competitive salary and annual reviews
- Opportunity to participate in Flo's performance incentive scheme
- Paid holiday, sick leave, and female health leave
- Enhanced parental leave and pay for maternity, paternity, same-sex and adoptive parents
- Accelerated professional growth through world-changing work and learning support
- Flexible office + home working, up to 2 months a year working abroad
- 5-week fully paid sabbatical at 5-year Floversary
- Flo Premium for friends & family, plus more health, pension and wellbeing perks
Diversity, equity and inclusion
Our strength is in our differences. At Flo, hiring is based on merit, skill and what you bring to the role – nothing else. We're proud to be an equal opportunity employer, and we welcome applicants from all backgrounds, communities and identities. Read our privacy notice for job applicants.