A period app that tells you how sure it is
Most period apps show a confident date even when they're guessing. Cycle shows its confidence honestly — "about 9 times in 10, it lands in this window" — and tells you what would sharpen it. And everything you log stays on your phone. No account. No server. Nothing collected, ever.
Coming soon to the · App Store
An engine that learns you
Predictions come from your own last six cycles, recent ones weighted more. Under three logged cycles it says "estimate" instead of pretending. Irregular cycles get a wide, honest window — never a fake date.
Logging that takes 15 seconds
Flow in real millilitres, pain from 0–10 in plain language, symptoms plus your own custom trackables. Backdate up to a week. No streaks, no guilt.
Patterns, not platitudes
"Your headaches cluster in the 3 days before your period — 8 of 10 cycles." Changes from your baseline get flagged as worth asking a doctor about.
A one-tap doctor report
Cycle history, pain trends, symptom frequency and questions to ask — as a PDF formatted for a 12-minute appointment.
Ask anything
An on-device Q&A that reads your own logs and answers "is this normal for me?" — and never diagnoses. Urgent symptoms get "see a doctor today", plainly.
The four phases, explained
Short, honest articles on each phase — what's happening, what tends to help, and where the evidence is thin. We say so when it is.
Privacy isn't a setting. It's the architecture.
Cycle has no account system, no server, no analytics, and makes no network requests at all. Your logs live in one file on your device — export them as JSON/CSV any time, or delete them truly. Our App Store privacy label reads "Data Not Collected" because that is literally true.