Selene is a daily guidance app that combines your menstrual cycle with the phases of the moon. It helps you understand your body’s natural rhythm alongside the lunar cycle — and what both mean for your energy, focus and wellbeing each day.

Selene is not a medical period tracker. It does not predict ovulation, fertility windows or health conditions. It is a rhythm and guidance app — it helps you tune into your cycle phases and understand their energy, not diagnose or treat anything.

Yes, Selene is completely free. There are no subscriptions, no in-app purchases and no hidden costs.

Selene works with four cycle phases:

Menstruation (days 1–5) — rest, release, inner wisdom.
Follicular (days 6–13) — rising energy, creativity, new beginnings.
Ovulation (days 14–17) — peak energy, magnetism, expression.
Luteal (days 18–28) — turning inward, sensitivity, completion.

Enter the first day of your last period and your average cycle length. Selene calculates which phase you are in today and how many days until your next period.

Not at all. You can enter any cycle length between 21 and 40 days. Selene adjusts the phase timing to your own rhythm.

Tap Edit cycle settings at the bottom of your cycle display, update the first day of your period and save.

Selene calculates the current moon phase based on the date, using the synodic cycle of 29.53 days from a known New Moon reference point. The calculation is accurate to within a day for any date.

New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter and Waning Crescent. Each carries its own energy and guidance.

Selene shows how your current cycle phase relates to the current moon phase. The White Moon cycle (menstruation on the New Moon) and the Red Moon cycle (menstruation on the Full Moon) are the two most well-known patterns — but every combination has its own meaning.

No. All data you enter is stored locally on your device only. Nothing is sent to any server. Selene has no backend, no account system and no data collection of any kind.

No. Selene does not connect to Apple Health or any other health platform. Your data stays entirely within the app.

No. There is no tracking, no analytics and no advertising. The app works entirely offline after installation.

Tap Edit cycle settings, clear the fields and save. Your data is removed immediately. Deleting the app also removes all stored data permanently.

Selene can send an optional daily reminder at 07:00 to open your reading. You can allow or deny this when first opening the app.

Go to iPhone Settings → Notifications → Selene and toggle them off.