Selene

Your body knows. Your phone should keep it to itself.

A period tracker that cannot share your data — not because we promise, but because the architecture makes it impossible.

Get notified at launch

Privacy

We say cannot, not won't.

On-device only

No accounts. No servers. No cloud. Data stays encrypted in Android Keystore, on your phone alone.

AES-256 encryption

All data encrypted at rest. The same standard used by banks and governments.

Zero third-party access

No analytics SDK. No advertising SDK. No tracking SDK. Nothing phones home.

Clinical frameworks

Built to NHS and NICE clinical frameworks.

PBAC

Pictorial Blood Assessment Chart — heavy menstrual bleeding scoring

PMDD

Premenstrual Dysphoric Disorder — DSM-5 diagnostic criteria

NICE NG73

Endometriosis — diagnosis and management guideline

PCOS

Updated May 2026 — Rotterdam diagnostic criteria

When a threshold is met, Selene surfaces a quiet prompt — not an alert. Just enough to start a conversation with your GP.

GP Summary

One tap generates a clinician-ready summary of your relevant data — cycle history, symptom patterns, framework flags. Ready for your appointment.

Why Selene exists

Cambridge called for this. Flo proved why.

2021

FTC finds Flo shared intimate health data with Facebook and Google without consent. Millions of users' period and pregnancy data was sent to third parties they never agreed to.

2025

Cambridge University researchers publish a call for a privacy-first period app — no accounts, on-device processing only. The specification is clear: data never leaves the phone.

2026

Selene. Built to the Cambridge specification. Every design decision traces back to those two words: on-device only.

Features

What Selene does.

Cycle tracking with clinical intelligence

Symptom and mood logging

NHS/NICE framework mapping

GP Summary export

One-off £3.99 — no subscription ever

Dark, calm design — no pink, no pastels

Launch

Be the first to know when Selene launches.

One email when Selene launches. Nothing else, ever.