Privacy Policy

1. Introduction

ViMind Technology (“we”, “us”, “our”) operates the Kobi English tutoring application. This Privacy Policy describes how we collect, use, and protect your personal information when you use our Service. By using Kobi, you agree to the practices described in this policy.

2. Information We Collect

Account information: When you sign in with Google, we receive your name, email address, and profile photo from your Google account.

Learning data: We store your placement test results, lesson progress, exercise responses, XP points, streak counts, and spaced-repetition card states to provide a personalized learning experience.

Usage data: We may log page visits and feature interactions to improve the Service. We do not currently use any third-party analytics service.

3. How We Use Your Information

We use the information we collect to:

• Provide and personalize your learning experience
• Generate AI explanations (we send only exercise context to the Claude API — your name and email are never included in AI prompts)
• Maintain your streak and progress tracking
• Communicate Service updates and improvements
• Improve and develop new features

4. Data Sharing & Third Parties

We do not sell your personal data. We share information only with the following third parties necessary to operate the Service:

• Google: For authentication via OAuth. Subject to Google's Privacy Policy.
• Anthropic: For AI-generated explanations. We send only exercise context (question text and your answer) — no personally identifiable information. Subject to Anthropic's usage policies.
• Vercel & Neon: For hosting and database infrastructure. Subject to their respective Data Processing Agreements.

5. Cookies & Tracking

Kobi uses cookies to keep you signed in and remember your preferences. The table below lists every cookie the Service sets.

Essential cookies cannot be disabled without breaking sign-in functionality. Preference cookies can be cleared in your browser settings at any time without affecting your ability to use the Service. Third-party cookies set by Google during OAuth are governed by Google's cookie policy.

We plan to add optional analytics cookies in a future update. When we do, we will ask for your explicit consent through an in-app cookie banner before setting any non-essential cookies.

6. Data Retention

We retain your account and learning data for as long as your account is active. If you request account deletion, we will delete your personal data within 30 days, except where retention is required by applicable law. Anonymized aggregate statistics may be retained for service improvement purposes.

7. Your Rights

Depending on your location, you may have the following rights regarding your personal data:

• Access: Request a copy of the data we hold about you.
• Correction: Request that we correct inaccurate data.
• Deletion: Request deletion of your account and all associated personal data.
• Portability: Request your learning data in a machine-readable format.
• Objection: Object to certain processing activities under GDPR or CCPA.

To exercise any of these rights, contact us at [email protected]. We will respond within 30 days.

8. Security

We implement appropriate technical and organizational measures to protect your data, including TLS encryption for all data in transit and restricted database access controls. AI prompts sent to the Claude API contain no personally identifiable information.

No method of transmission over the internet is completely secure. While we strive to protect your data, we cannot guarantee absolute security.

9. Contact

For privacy questions or to exercise your rights, contact us at [email protected]. ViMind Technology, Vietnam.