Privacy Policy

Summary

Cerno is designed to keep most learning data on your device. If you use hosted sync or AI features, the App sends the information needed to provide those features to our service providers. We do not sell personal information, use advertising SDKs, or use your data for targeted advertising.

Information we handle

Depending on the features you use, we may handle the following information:

• Learning content and activity. This can include generated drill topics, drills, submitted answers, structured reasoning, scores, critiques, preferences, and progress. Most of this information is stored locally on your device.
• Pseudonymous account and usage data. When hosted features are enabled, the App creates an anonymous Supabase account identifier and processes feature requests, timestamps, and daily usage counts to provide synchronization, protect the service, and enforce feature limits.
• Optional AI-provider API key. If you choose to enter your own OpenAI, Anthropic, or Google AI API key, it is stored on your device using the operating system’s secure storage. The key is sent to the provider only to validate it or make a request you initiate. Rapki does not store your optional API key on its servers.
• Support messages. If you email us, we receive the information you include, such as your email address and message.
• Technical information. Our hosting and service providers may process IP address, request metadata, and security logs when you use hosted services or visit this site. We do not use this information for advertising or cross-app tracking.

How information is used

We use information only to:

• operate, secure, and improve the App and requested features;
• generate and evaluate drills and provide AI feedback when you request it;
• sync your learning records when hosted sync is available;
• respond to support requests; and
• comply with law and prevent fraud, abuse, and security incidents.

We do not sell personal information or use it for interest-based advertising.

When information leaves your device

Hosted Cerno features use Supabase to create and manage the anonymous session, synchronize learning records, and operate the service. For hosted AI feedback and generation, the relevant request content is processed by the AI provider selected for the hosted service. If you use your own API key, your request is sent directly to that provider. These providers process information under their own terms and privacy policies.

We use Vercel to host this website. We may disclose information when required by law or when necessary to protect users, our services, or the public. We do not otherwise share your information for third parties’ independent marketing purposes.

Data stored on your device

The App stores its local database, drafts, progress, preferences, and any optional API key on your device. You can remove local App data, including the stored API key, using Reset all local data in Cerno’s Settings. Uninstalling the App normally removes its local data, subject to your device and backup settings.

Retention and deletion

We keep information only as long as needed to provide the App and meet legal, security, or operational obligations. Locally stored information remains under your control until you reset the App data or uninstall the App.

To request deletion of information associated with a hosted Cerno session, use our data-deletion request page or email privacy.cerno@rapki.com with the subject line “Cerno data deletion.” We may request information needed to verify and process the request. Deleting hosted data does not remove information held by an AI provider under that provider’s own retention practices.

Security

We use reasonable technical and organizational measures intended to protect information. No service or method of transmission is completely secure, so we cannot guarantee absolute security.

Children

Cerno is not directed to children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided personal information to us, contact us and we will take appropriate steps to address it.

International users

Your information may be processed in countries where Rapki or its service providers operate. Depending on where you live, you may have rights to request access to, correction of, or deletion of personal information. Contact us to make a request.

Changes to this policy

We may update this policy as the App changes. We will post the revised version here and update the effective date.

Contact

For privacy questions or requests, email privacy.cerno@rapki.com.