Willa: Personal PCOS Companion

Inspiration

I was diagnosed with PCOS at age 12. Ever since, I've had countless doctor's visits and tests, all ending in the same theme "lifestyle changes".

When ChatGPT came out, I was quick to download the app on my phone. I had a separate chat named PCOS. I shared test results, symptoms, what I was eating, how many steps I was getting, and questions about how I was feeling at different points in my cycle.

It definitely made a difference. PCOS, weight gain, hormonal changes, and unwanted hair growth are so stigmatised.

It was good to have a place for these conversations.

And, I learnt a lot about the way my body works. Once the shame went away, I started focusing on things I could actually influence: eating more fibre, moving more, and finding routines that worked with my energy, cycle, and time.

While using ChatGPT was much better than not using it, there were a lot of things that could've been better. I'd have to sometimes keep sending the same test results, I had to keep giving it the same context because it would keep forgetting. I'd have to initiate conversations and take the lead. It was better than using a traditional PCOS apps. I did not want another place to track my weight, which had already caused me a lot of mental anguish. I did not need an app deciding whether I was “late” when I could record my cycle in Apple Health. I wanted support that helped me focus on day to day choices, not another dashboard telling me what I should be doing.

That is why I am building Willa. Doctors are important, but they are not there after a long day when you are deciding what to eat, trying to understand a symptom, or struggling to keep momentum. Willa is meant to support those day-to-day moments, helping women with PCOS feel more capable of managing their health without pretending to replace their doctor. Willa helps making "lifestyle changes" an actual part of your life.

What it does

Willa is a non-judgmental health coach for women with PCOS. It remembers what she has tried, helps her spot patterns over time, and supports realistic day-to-day choices without pretending to be her doctor.

Instead of focusing on weight or rigid tracking, Willa helps women focus on what they can realistically do today. That might mean choosing a meal after a long day, noticing how a routine is affecting their symptoms, building small habits that fit their life, or preparing better questions for a doctor’s appointment.

Willa is designed to live in the space between appointments: a supportive companion that remembers the context, helps turn general health advice into practical next steps, and makes it easier to keep going without shame.

How we built it

The app is built with Expo (React Native) and uses Convex as the backend. For our chat, we're using the Convex AI Agent component. The AI is passed through Vercel AI gateway.

We started with a handwritten project setup for linting and formatting. And after that, everything was designed and built by Codex.

Challenges we ran into

The biggest challenge was to make Willa truly useful as a guide for women living with PCOS. We didn't want this to be a generic chatbot, so a lot of effort went into making sure its behavior was optimized to help our users.

Accomplishments that we're proud of

We started very late, on July 18th. And still managed to ship the app before the deadline. We're very proud of the way the app actually takes memories from the chat, and the way we've designed the prompt to make sure that it takes in stuff that is valuable. Janet doesn't really have any coding experience, and she was the one who did the UI (using Codex). She's really proud of that.

What we learned

Well, we started working on this literally two-three days before the deadline, and we learned that it's actually really fast and quick to make something thats so useful using Codex and GPT 5.6 - that was crazy!