Pink Moon

Private by design. Encrypted lunar cycle tracking.

A period, pregnancy and menopause tracker that encrypts your health data on your phone before it’s ever backed up. Only you hold the key, so not even we can read it or hand it over. Six modes support you from your cycle through pregnancy, postpartum and menopause. Synced with the moon.

Status: Live on iOS & Android (US & Canada)
Platforms: iOS · Android

The problem

Period and pregnancy data is some of the most sensitive data people have, and most trackers can read it, hand it over, and sell it. Most cycle trackers appear clinical in nature. Pink Moon users love seeing their cycles synced with the moon.

My role

Founder and sole engineer
Encryption architecture
App
Website
Legal readiness
Beta program
Launch

Key decisions & results

A zero-knowledge architecture
Health data is encrypted on the phone with a key derived from the user’s PIN (AES-256-GCM, Argon2id key hierarchy) before it’s backed up, and document IDs are hashed, so the server stores nothing it can read. The trade-off is deliberate: users get a 24-word recovery phrase, and if they lose both it and their PIN, their data is gone for good, even for me. The privacy policy and terms say so plainly.
No third-party analytics
Dropped third-party analytics to keep the privacy promise honest, and learned from beta surveys and interviews instead.
Six modes, one app
Built six modes (period, trying to conceive, pregnancy, postpartum, perimenopause, menopause), each with personalized content, so users can stay in one private app for life.
Beta, waitlist and launch
Took Pink Moon from idea to the App Store and Google Play in under four months, including attorney, engineering and medical content reviews, a 28-person beta with surveys and interviews, and a 100-person organic waitlist. Launched Aug 31, 2026.
Organic short-form video
Short-form videos reached 2.4M+ organic views.