Privacy Policy

Last updated: August 2026

Lightsidian is built local-first and private. Your notes are yours — they live on your device, you can export them at any time, and we never sell your data.

The short version

• Your notes stay on your device. Cloud sync is optional and only happens if you sign in.
• We show no ads and never sell your personal data.
• You can use Lightsidian fully without an account.
• You can export everything to plain Markdown, and delete your data, whenever you want.

What we handle, and why

Your notes and content. The notes you write — titles, body text, tags, folders, attachments (photos, audio, files), tasks and reminders — are created and stored on your device. Without an account they never leave it. When you sign in, they are also stored in your own account-protected space in the cloud so they can sync across your devices.

Your account. If you choose to sign in with Google, sign-in is handled by Firebase Authentication (a Google service). We receive a basic account identifier and email so we can create and protect your personal space. We do not receive your Google password.

Calendar. If you connect Google Calendar, the access token is used only while syncing your events and is not stored on our servers.

What we don't do. We don't sell your data, we don't show advertising, and we don't build advertising profiles about you.

Where your data is stored

On your device first. When you are signed in, your notes and media are stored in Google Firebase (Realtime Database and Storage, EU region) under your account, readable only by you. Authentication is handled by Firebase Authentication (Google). These Google services process data on our behalf under Google's own privacy terms.

Your choices and rights

• Use it without an account — everything works locally, nothing is sent to the cloud.
• Export any time — export your whole vault to plain Markdown files and folders.
• Sign out whenever you like.
• Delete your data — deleting a note removes it from your device and from the cloud. To erase all of your cloud data, sign in and delete your notes, or email us to request full deletion of your account data.

Data retention

Local data stays until you delete it or uninstall the app. Cloud data stays in your account until you delete it or ask us to remove your account data. Deletion requests are honoured promptly.

Children

Lightsidian is not directed at children under 13, and we do not knowingly collect personal information from them.

Changes to this policy

If we make material changes, we will update this page and the "last updated" date above.

Contact

Questions, or a data-deletion request? Email hello@lightsidian.com.