Calendula is a modern, open-source calendar app for Android. It works directly on the system calendar provider, so any source synced to your device — Nextcloud via DAVx5, Google, local, WebCal subscriptions — shows up automatically, and changes you make sync back the same way. Create, edit and delete events, including recurring events with scoped changes (only this event / this and all following / the whole series) and a simple repeat picker. Calendula also delivers your event reminders as notifications — tap one and you're on the event. Optionally, show your contacts' birthdays, anniversaries and other special dates in your calendar. You turn this on yourself; contacts are read only on your device, are never uploaded, and are never changed — Calendula only mirrors the dates into local calendars you fully control. The differentiator is the design: real Material 3 Expressive throughout, with dynamic color, expressive motion, and expressive shapes. Privacy: zero telemetry, no analytics, no network access — your data never leaves the device.