Legal

Privacy policy

Last updated 19 August 2026

What we collect

Nothing. We operate no backend, no account system and no analytics. We do not receive your cycle data, your device identifiers, your location, your contacts or your usage patterns, because the app has no mechanism to send them.

What the app stores on your device

• The dates you tap to log the start and end of a period.
• Your settings: cycle length, period length, luteal phase, week start, contraception mode, reminder time and whether the app lock is on.
• Predictions derived from the above. These are calculated on the device, every time, from the data already on it.

This information is held in a local SQLite database inside the app’s private storage area, which Android isolates from other apps.

Health data

Menstrual and cycle information is sensitive personal data. That is precisely why the app is built without a network layer: data that is never transmitted cannot be intercepted, subpoenaed from us, sold, or exposed in a breach of our systems. We cannot hand over what we have never held.

Notifications

Period reminders are local notifications. Your phone calculates the date from the prediction already stored on it and schedules the alert itself. No push service, no push token and no notification content ever reaches us or a third party.

Export and backup

The export feature writes an unencrypted JSON file containing your logged periods and settings, and then hands it to Android’s share sheet so you can choose where it goes. Once you send that file somewhere — email, cloud storage, another device — it is governed by whatever service you chose, not by this policy. Treat the file as you would any other sensitive document.

App lock

If you enable the app lock, unlocking uses your device’s own fingerprint, face or PIN check. The app is told only whether the check passed. Your biometric data never leaves the secure hardware on your phone and is never visible to us or to the app.

Third parties

The app contains no advertising SDKs, no analytics SDKs and no social login. It makes no third-party network requests while you use it.

The one exception is app updates: the app can check our update service for a newer version of its own code. That request carries the technical information needed to serve the correct update — such as the app version and platform — and no cycle data.

Children

Lumen Cycle is not directed at children under 13, and we do not knowingly collect data from anyone, of any age, since we collect no data at all.

Your rights

Rights of access, correction, deletion and portability are usually exercised by asking a company for your data. Here they resolve directly on your device: everything is already in your possession, “Export my data” provides portability, and “Clear all data” deletes every logged period immediately. Uninstalling the app removes the database along with it.

Changes

If this policy changes materially we will update the date at the top and, where the change affects how your data is handled, say so in the app.

Contact

Questions about this policy: [email protected] or +234 806 886 2866.