§Legal

Lumen Privacy Policy

Last updated: 3 June 2026

This policy describes how Lumen, a daily planner app published by Halcytron (SAS), handles your information. The data controller is Halcytron; see the legal notice for our identity and contact details.

Accounts

You can use Lumen with an anonymous account that is created automatically and identified by a random ID, not your name. If you choose to secure or sync your account, you can sign in with your email address using a one-time code. In that case we process your email to authenticate you.

Data we process

  • Your planning data: categories and items (tasks, notes, dates) you create, stored so they sync to your account.
  • Email address: only if you sign in with email.
  • Push notification token: if you enable reminders or the morning briefing, so we can deliver those notifications.
  • App preferences: settings and language.

Lumen does not include third-party advertising or analytics trackers.

AI features

Some features (such as the morning briefing and "organize") use AI. When you use them, the relevant planning content is sent to our AI processor, OpenRouter, to generate suggestions. This content is processed to return a result and is not used to show you ads. AI output can be imperfect, so please review it before relying on it.

Where your data is stored (sub-processors)

We rely on the following providers to run Lumen:

  • Supabase: database, authentication, and backend hosting. Your account and planning data are stored in the European Union (Frankfurt, Germany).
  • OpenRouter: AI processing for the features above.
  • Expo: delivery of push notifications.
  • Apple App Store / Google Play: app distribution and any purchases.

Your account and planning data are stored in the European Union (Frankfurt). Some processors (the AI provider OpenRouter, push delivery via Expo, and the app stores) may process limited data outside the EEA; where that happens, appropriate safeguards such as the EU Standard Contractual Clauses are applied.

Purchases

Any paid features are processed by the App Store or Google Play. Halcytron does not receive your payment card details.

Retention & deletion

We keep your data while your account exists. You can delete your account and associated data from within the app, which removes it from our backend. You may also uninstall Lumen at any time.

Your rights

Under the GDPR you may request access, correction, deletion, or portability of your personal data, and may object to or restrict certain processing. Contact contact@halcytron.com. You also have the right to lodge a complaint with the French data-protection authority (CNIL).

Children

Lumen is not directed at children under 15.

Contact

Privacy questions: contact@halcytron.com.