Kokoro Learn ("we", "us", or "our") operates the website kokoro-learn.online and any associated mobile applications and services (collectively, the "Service"). This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use the Service.

By accessing or using the Service, you agree to the terms of this Privacy Policy. If you do not agree, please do not use the Service.

1. Information We Collect

1.1 Information Received from Third-Party Authentication Providers

We offer sign-in through third-party providers such as Google (via OAuth). When you authenticate through these services, we receive the following information directly from the provider:

• Name
• Email address
• Profile picture (if provided by the provider)

You may also choose to edit or provide your name manually after registration.

1.2 Information You Provide or Generate While Using the Service

While using Kokoro Learn, we collect and store:

• Learned vocabulary words and flashcards
• Personal and public word collections/decks (you decide whether a collection is private or publicly visible)
• Memorization progress, review history, and spaced repetition system (SRS) data
• Learning statistics derived from your activity
• Study streaks (consecutive days of activity) and related login/activity timestamps

1.3 Automatically Collected Information

We may automatically collect certain usage data, including IP address, browser/device type, and interaction data to maintain and improve the Service.

We do not collect sensitive personal information such as health data, racial or ethnic origin, or financial information.

2. How We Use Your Information

We use the collected information to:

• Provide, maintain, and improve the Service (including tracking your learning progress, calculating statistics, and maintaining streaks)
• Personalize your learning experience
• Enable public sharing of collections (if you mark them as public)
• Authenticate your account and manage user sessions
• Communicate with you regarding important updates (if necessary)
• Analyze aggregate usage trends (without identifying individual users)
• Comply with legal obligations

3. How We Share Your Information

We do not sell your personal information to third parties.

We may share your information in the following limited circumstances:

• With service providers: Hosting providers, authentication services (e.g., Google), and technical partners who help us operate the Service. These parties are contractually obligated to protect your data.
• Public collections: Any word collections you mark as "public" will be visible to other users of the Service.
• Aggregated or anonymized data: We may share anonymized statistics about learning trends for marketing or research purposes.
• Legal requirements: If required by law, court order, or government request.
• Business transfers: In the event of a merger, acquisition, or sale of assets, your information may be transferred as part of that transaction.

4. Data Retention

We retain your personal information for as long as your account is active. You may delete your account at any time through the Service settings, which will permanently delete your personal learning data, collections, progress, and streaks.

We may retain anonymized or aggregated data indefinitely for analytical purposes.

5. Your Rights and Choices

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

• Access, correct, or delete your personal information
• Opt out of certain data processing (where applicable)
• Withdraw consent for OAuth authentication

To exercise these rights, please contact us at the email address below. We will respond within 30 days.

6. Security

We implement reasonable administrative, technical, and physical safeguards to protect your personal information. However, no method of transmission over the Internet or electronic storage is 100% secure.

7. Children's Privacy

The Service is not intended for children under 13 years of age. We do not knowingly collect personal information from children under 13. If you are a parent or guardian and believe we have collected information about a child, please contact us immediately so we can delete it.

8. International Data Transfers

Your information may be transferred to and processed in countries outside of your jurisdiction, including the United States. We ensure appropriate safeguards are in place for such transfers.

9. Changes to This Privacy Policy

We may update this Privacy Policy from time to time. We will notify you of any material changes by posting the new policy on this page and updating the "Last Updated" date. Your continued use of the Service after such changes constitutes your acceptance of the revised policy.

10. Contact Us

If you have any questions or concerns about this Privacy Policy, please contact us at:

Email: support@kokoro-learn.online