Privacy policy

How Marrow Calendar treats your information

Effective date: 8 September 2026 · Last updated: 18 October 2026

This policy explains what Marrow Calendar ("the app", "we") does with your information. It is written to be read, not to be survived. If anything here is unclear, write to us at contacto@marrowcalendar.com.

1. Data the app stores on your device

The app keeps the following locally, using the operating system's standard storage (UserDefaults) and, where applicable, your iCloud calendar database:

So that the Home and Lock Screen widgets can show your agenda and your look, the app shares with them — only inside your iPhone, through an Apple app group — your chosen look, your language, whether you have Plus and the colours of your events. The widgets read your events straight from the system calendar, just like the app does.

We cannot see any of this. It is not transmitted to us. Attached files do not sync between your devices — they stay on the iPhone where you added them — and are deleted automatically if you delete the event or the app.

2. Calendar access

The app asks for full access to your calendar so it can display, create, edit and delete events — that is the core purpose of the app. If you decline, the calendar screens are unavailable but the rest of the app (the date and the historical fact) still works.

Calendar data is read from and written to the system Calendar store. The app does not copy your events anywhere else.

3. Notifications

Marrow can send you two kinds of notification, always local: the daily fact-of-the-day nudge (if you turn it on in Settings) and alerts for your events, so they arrive even when the Calendar app's notifications are off. They are scheduled and fired on your iPhone, without going through any server of ours. You manage the permission in iOS Settings and can withdraw it whenever you like.

4. Place search

When you type a location into an event, the text you type is sent to Apple Maps (MKLocalSearchCompleter / MKLocalSearch) to return address suggestions. This is handled by Apple and subject to Apple's privacy policy. If you never add a location, no search is performed.

5. The "fact of the day"

The historical facts shown in the app (one for every day of the year, in all nine languages of the app) are bundled inside the app. Displaying them requires no network request and sends nothing anywhere. Each fact links to a Wikipedia article; opening that link loads it in your browser, at which point the Wikimedia Foundation Privacy Policy applies.

6. Purchases

Marrow Plus is sold through the App Store as a single, one-time purchase (no subscription). The transaction, your payment method and the receipt are handled entirely by Apple. We receive only anonymous, aggregated sales information from Apple; we never see your payment details. Restoring a purchase uses Apple's StoreKit and your Apple ID; it does not create an account with us.

7. What we do NOT do

• No accounts, logins or passwords.
• No ads and no advertising SDKs.
• No first-party analytics, crash SDKs or fingerprinting.
• No selling, renting or trading of personal data.
• No profiles built about you by us.

8. Children

The app is not directed at children under 13 (or the equivalent minimum age in your country). We do not knowingly collect personal data from children.

9. Your rights

Because we hold no personal data about you on any server, there is nothing for us to export or delete on our side. You are in control directly:

• Calendar data: manage it in the Calendar app or in Settings › Calendar.
• App preferences and colours: delete the app to remove them from the device. Turn notifications off in iOS Settings.
• Attached files: remove one from inside the event, or delete the event itself; either way the file is erased from the device.
• Purchases: managed in your App Store account.

If your jurisdiction (e.g. the EU/EEA, UK, or California) grants you specific rights over personal data, you may contact us at contacto@marrowcalendar.com and we will respond as required by the applicable law. The controller for any such processing is Mikel Albistegui Aguirre, Barrio Olabarrieta 74, Caserío Aiastui 74, 20560 Oñati (Gipuzkoa), España.

10. Data retention

Preferences persist on your device until you change them or delete the app. We keep no personal data, so we have no retention period to state for our side.

11. Changes to this policy

If we change how the app handles data — for example, if a later version enables cross-device sync of your preferences or any form of advertising — we will update this page, change the "Last updated" date, and note significant changes in the App Store release notes.

12. Contact