✦ Kesla — Privacy Policy

The short version

Kesla is built to be privacy-preserving. Your learning data stays on your device, we don't require an account, we don't show ads, and we don't track you across apps or sell your data. The only time information leaves your device is to generate a lesson with the AI engine you choose, or to process a subscription through the app store.

What we handle

• On-device learning data. Your skills, progress, streaks, quiz results, and spaced-repetition cards are stored locally on your device. We do not receive or store this data on our servers.
• Lesson requests. When you generate a lesson with a premium AI engine, the topic you entered (and the difficulty/engine selected) is sent to our backend, which forwards it to the AI provider you chose to create the lesson. By default we do not log the topic or the generated content.
• Subscription status. Purchases are handled by Apple or Google. Through our billing provider (RevenueCat) we receive your subscription/entitlement status (e.g. "Pro active"), not your payment card details.
• Minimal diagnostics. Our backend keeps coarse operational logs (timestamps, request paths, status codes, and moderation category when content is blocked). These do not include your lesson topics or generated content.

What we do NOT do

• No advertising and no ad tracking.
• No selling or sharing of personal data for advertising.
• No cross-app or cross-site tracking; no advertising identifiers.
• No user accounts, so no name/email is required to use the app.

Third parties

To provide the app we rely on: the AI provider(s) you select (which may include Anthropic, OpenAI, Google, xAI, GitHub/Microsoft, or DeepSeek) to generate lesson content; Apple and Google for app distribution and subscription billing; and our billing and hosting providers. Your lesson topic is processed by the AI provider you choose under that provider's terms and privacy policy. We encourage you to review those policies.

Children

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

Your choices & rights

Because your learning data lives on your device, you control it directly — you can erase it anytime with Reset all progress in the app, or by deleting the app. Depending on where you live (e.g. the EEA/UK under GDPR, or California under CCPA/CPRA), you may have rights to access, correct, or delete personal data and to not be discriminated against for exercising them. Since we hold essentially no personal data server-side, most requests are satisfied on-device; for anything else, contact tc@matador-llc.com.

Data retention & security

On-device data persists until you delete it. Our backend is stateless and retains no lesson content. We use industry-standard measures (encryption in transit, restricted access to keys) to protect the limited data we handle. No method of transmission or storage is 100% secure.

International transfers

The AI and infrastructure providers we use may process data in the United States or other countries. Where required, we rely on appropriate safeguards for such transfers.

Changes

We may update this policy. Material changes will be reflected by updating the date above and, where appropriate, an in-app notice.

Contact

Matador Vanguard LLC · tc@matador-llc.com · https://kesla.app