Moon Theory

Moon Theory is a beautifully simple, fully private moon companion. Everything is computed right on your device — no account, no sign-in, no servers, and nothing about you ever leaves your phone.

Open it tonight to see exactly where the Moon is in its cycle: a live illuminated glyph, the precise illumination percentage, the current phase name, and tonight's moonrise and moonset for your location. Countdowns show exactly how long until the next new and full moon.

FEATURES

• Today — a large, live moon glyph drawn from the real illuminated fraction, plus illumination %, phase name, and today's moonrise and moonset in your local time.

• Tonight — an at-a-glance look at what the sky is doing tonight.

• Calendar — a month grid with a phase glyph on every day; new, quarter, and full days are marked. Tap any day for its phase and rise/set times.

• Reminders — optional local notifications for the moments that matter: New, First Quarter, Full, and Last Quarter, each with your own lead time.

• Your location, your way — use GPS or enter coordinates by hand.

• 12- or 24-hour time.

PRIVATE BY DESIGN

Moon Theory works entirely offline after your first location fix. There is no backend and no network call in the core app. Your coordinates are used only on your device to compute moon times — never transmitted, never stored remotely, never shared. No analytics. No tracking. No ads.

Whether you're planning a night hike, chasing the full moon, or just love knowing what the sky is doing, Moon Theory keeps the Moon at your fingertips — quietly, accurately, and privately.