Coming early 2027 for iOS and Android
Understory is a journal for living with PMOS (formerly PCOS). Tell it about your day. Your phone and watch add the rest. We are building it to help you see what sits behind your good days and your hard ones.
Why we are building it
PMOS affects about 12% of adult women.1 It disrupts hormones, metabolism, fertility and mental health.2 It also raises the long-term risk of type 2 diabetes, heart disease, anxiety and depression.2,3,4
Good management lowers these risks.2 But managing PMOS well means knowing what is working. Treatments take weeks to act. Cycles are irregular. A new treatment often starts alongside changes to food and sleep. It is hard to tell what sits behind a bad week.
12%
of adult women have PMOS.1
1 in 3
waited more than two years for a diagnosis.5
47%
saw three or more health professionals before they were diagnosed.5
The diagnosis figures come from one survey of 1,385 women, mostly in North America and Europe.5
So many people work out what helps through long trial and error. Understory is our attempt to shorten that.
The app
A journal only helps if you keep using it. So Understory asks for very little.
Speak, type or tap. Write as much or as little as you like. Food and weight logging are optional, and you can hide them.
Sleep, heart rate, steps and screen time arrive on their own. No watch? Understory still works with your entries and your phone.
Every day shows your sleep, mood, energy and steps. Each one sits next to your last week. You are compared with yourself, not with an average of other people.
Understory does not assume a regular cycle. Your next period shows as a range, like 6 to 10 days, not a single date.
What we are building: In development
Insights are still in development. These are the principles we are building them on.
Each change is compared with what is normal for you. Understory does not lean on averages from other women.
Sleep, food, exercise, stress, medicine and your cycle affect each other. Some effects show up days later. Understory looks at them together.
A pattern appears only when the evidence is consistent and repeated. Understory tells you how sure it is.
Privacy
Health data is personal. This is how Understory handles it.
You can export or delete your data at any time.
We never sell your data.
Voice entries are transcribed on your phone. The recording is then deleted and never leaves your device.
Your data is encrypted and stored in your own region.
Understory is designed to comply with the New Zealand Privacy Act 2020.
The team
We are a two-person technical team. We own the whole pipeline, from raw sensor data to the explanations you see. That covers sensing, machine learning, language processing, software engineering, UX design and cloud infrastructure.
Building the AI engine
Nastaran is a part-time research fellow at the Auckland Bioengineering Institute. She works on physiological sensing and AI. She has seven peer-reviewed papers and a peer-reviewed open-source sensing library. She has collaborated on a diabetes management app and worked for more than five years as a software engineer in banking. She lives with PMOS herself.
Building the platform
Aidin is a senior full-stack engineer with more than 15 years’ experience, including leading software development in banking. He owns the platform: the app, UX design, cloud infrastructure and data pipelines.
Questions, feedback or ideas? We would like to hear from you.
understory.tech