One Big Calendar: Period

Menstrual, ovulation, and PMS phases sit on the same month grid as your real meetings. Log symptoms and mood in one tap. Private, on-device.

Your calendar knows your meetings. It should know your cycle too.

One Big Calendar puts your whole life on a single screen: your real events and your menstrual cycle, side by side. Instead of juggling a period tracker in one app and your schedule in another, you see how your body and your week line up — and plan accordingly.

THE PROBLEM Cycle apps live in their own world. Calendars pretend your energy is the same every day. So you end up booking a brutal week during your period, or forgetting to log because the tracker is one more app to open. One Big Calendar closes that gap.

WHAT YOU GET • A clean month, week, and day calendar that reads and writes your existing iOS calendars (iCloud, Google, Outlook — anything already on your iPhone). • Your cycle phases — menstrual, follicular, ovulation, luteal — shown right on the dates. • Period logging with flow intensity, plus a prediction for your next period and a confidence level that sharpens as you log. • One-tap logging for symptoms, mood, weight, and intimacy. • Color categories you can map to your real calendars, so work, personal, and health stay visually separate. • Insights that translate your data into plans — "energy usually dips now, protect your evenings" — instead of just charts. • Apple Health sync: import your existing cycle and weight history, and write your logs back so every health app stays in step. • A home-screen widget for your day at a glance.

PRIVATE BY DESIGN Your data lives on your device. There are no accounts, no ads, and nothing is ever sold or sent to us — we have no server to send it to. That's it.

NOT A MEDICAL DEVICE Predictions and phases are estimates based on the data you log. One Big Calendar is for planning and awareness — it is not a medical device and is not intended for contraception or fertility planning.

WHO IT'S FOR Anyone who menstruates and is tired of running their life out of two apps that don't talk to each other. If you want your schedule to respect your body, this is your calendar.

Your calendar. Your cycle. One place.

TERMS & PRIVACY Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://hellogoodday.com/onebigcalendar/privacy

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