02 · app
Pawriod
A private period tracker with a dog for a mascot. It predicts the next period and the fertile days, works offline, and keeps everything on the phone behind a PIN.
The mess
The period apps I found weren't private: they keep your data on their servers. I wanted one where it never leaves the phone.
What I built
Two versions that read the same backup file. A single HTML file for the computer: fully offline, saved only in that browser. And an iPhone home-screen app: the data is encrypted with a PIN (AES-256), never leaves the phone, and the app blocks connections to any other site.
What it does
- Today: days until the next period, cycle day and phase
- Calendar: period, predicted, fertile and ovulation days
- Stats: average cycle and period length, cycle history
- Lock: a PIN screen; the app locks itself after a minute in the background
- Reminders: the next dates go into the phone's calendar, with discreet titles
Made with
- Claude
- HTML / JavaScript
- Web Crypto
- Service worker
- Cloudflare Pages