Privacy Policy

The controller of your personal data is the team operating the Kairn platform, reachable at kairnsupport@gmail.com. For any question about this policy or your rights, email us with the subject line "Personal data".

Depending on how you use the service, we may process:

• Account: email address, display name, password (hashed by our authentication provider), language preferences, technical account identifiers.
• Learning activity: progress, quiz results, aggregated study sessions, content views to the extent needed to run the service.
• Billing: via our payment provider (e.g. subscription status, customer or subscription identifiers on their side) — we do not store full card numbers on our application servers.
• Technical data: logs and events required for security and troubleshooting (e.g. timestamps, application session identifiers, event types).
• Support: content of messages you send through the channels we provide.

We use this data to:

• Provide and secure the service (performance of a contract / pre-contractual measures; legitimate interests in security).
• Manage subscriptions and billing (performance of a contract; accounting and tax obligations where applicable).
• Communicate about the service (account-related messages, email verification) — no unsolicited commercial prospecting without an appropriate legal basis.
• Measure and improve product usage through aggregated or pseudonymised analytics where implemented (legitimate interest, with appropriate safeguards).
• Comply with legal obligations and defend our rights in disputes.

We use technical mechanisms required for the site and session to work (e.g. cookies or local storage related to authentication and preferences). There is no third-party advertising cookie banner of the "social network" type on the flows described here; any change will be reflected in this policy.

Data is hosted and processed by providers acting on our instructions, including:

• Google Firebase / Google Cloud (authentication, database, application hosting) — see Google's documentation and commitments.
• Stripe (payments and subscriptions).
• Vercel or equivalent for hosting and delivery of the web application.

Some providers may be located outside the European Economic Area. Where that applies, we rely on mechanisms provided by law (e.g. standard contractual clauses and supplementary measures as appropriate).

We keep data only as long as necessary for the purposes above, then archive or delete it within reasonable timeframes (e.g. account data while the account is active; billing data according to legal requirements; technical logs for a limited period consistent with security).

We implement appropriate technical and organisational measures (restricted access, encrypted connections, professional hosting). No system is perfect; please protect your credentials and report suspected misuse.

Subject to legal exceptions, you may exercise rights of access, rectification, erasure, restriction, objection, and data portability by writing to kairnsupport@gmail.com. You may also lodge a complaint with a data protection authority (e.g. CNIL in France or the Swiss FDPIC, depending on your situation).

The service is intended, as per our Terms of Use, for adults or minors under the responsibility of a legal guardian. If you believe a minor has provided data without authorisation, contact us so we can take appropriate steps.

We may update this policy to reflect changes to the service or legal requirements. The date at the top will be revised; material changes may be communicated by email or through the Platform.

Questions about this policy or your data: kairnsupport@gmail.com