Privacy Policy

Last updated: July 27, 2026

Locklune is designed so that your data never leaves your device. This policy explains what that means in practice. The short version: we collect nothing.

Data we collect

None. Locklune has no account system and no servers. We do not collect your name, email, phone number, location, device identifiers, or any usage analytics. We never see your cycle data or your PIN.

Where your data lives

All information you enter (period dates, flow, mood, symptoms and notes) is stored only on your device, inside a database encrypted with AES-256 (SQLCipher). The encryption key is derived from your PIN and is held in your device's secure hardware keystore. Without your PIN, the data is unreadable.

No network, no third parties

The app contains no networking code and no third-party SDKs, advertising, or analytics. There are no cookies and no trackers. Your data is never transmitted, sold, or shared, because it is never sent anywhere in the first place.

Notifications

If you enable reminders, they are scheduled locally by your operating system based on on-device predictions. No push service is used and no data is sent to schedule them.

Recovery

Because your data is encrypted with your PIN and we hold no copy of anything, a forgotten PIN means the data cannot be recovered, by you or by us. This is a deliberate security trade-off.

Deleting your data

You can erase everything instantly from within the app (Settings, then Erase all data), or by deleting the app. There is nothing stored elsewhere to delete.

This website

The pages of this site are served without cookies, analytics, or third-party scripts. Fonts are self-hosted, so loading a page makes no third-party requests. Standard server access logs may be kept briefly by the hosting provider for security, but this site sets no identifiers and runs no tracking of its own.

If you use the contact form, the name, email and message you submit are sent to our support inbox (via our email provider, Brevo) so we can reply. They are used only to respond to you.

Children

Locklune does not knowingly collect data from anyone, including children, because it does not collect data at all.

Changes

If this policy changes, the “last updated” date above will change with it. Since we collect no contact information, please check back here for updates.

Contact

Questions? Use the contact form on our support page.