1. Introduction

Nysphere ("we," "our," or "us") operates the Minute Chinese iOS application ("App"). This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our App. Please read this policy carefully.

By using the App, you agree to the collection and use of information in accordance with this policy.

2. Information We Collect

Account Information

When you create an account, we collect:

• Email address
• Password (stored as a secure hash — we never store plaintext passwords)

Study Data

To power your learning experience and sync progress across devices, we collect:

• Study session history (sentences reviewed, ratings given, timestamps)
• Playlist names and contents you create
• User preferences and app settings

Usage Information

We may collect anonymized information about how you interact with the App, such as features accessed and session duration, to help us improve the service.

Device Information

We may collect information about your device, including model, operating system version, and unique device identifiers, solely for diagnostics and compatibility purposes.

3. How We Use Your Information

We use the information we collect to:

• Create and manage your account
• Sync your study progress and preferences across devices
• Provide, operate, and improve the App
• Respond to your support requests
• Send transactional emails (e.g., password reset)
• Detect, prevent, and address technical issues or abuse
• Comply with legal obligations

We do not use your data for advertising or sell it to third parties.

4. Data Storage and Security

Your data is stored on secure servers provided by Amazon Web Services (AWS) and MongoDB Atlas, both of which maintain industry-standard security certifications. We use encryption in transit (TLS) and at rest for sensitive data.

Authentication is handled by Supabase, an industry-standard authentication provider. Passwords are never stored in plaintext.

While we implement appropriate technical measures, no method of transmission over the internet is 100% secure. We cannot guarantee absolute security.

5. Data Retention

We retain your personal data for as long as your account is active. You can delete your account and all associated data at any time directly within the App. Deletion is processed immediately, except where we are required to retain certain information by law.

6. Third-Party Services

The App uses the following third-party services, each governed by their own privacy policies:

• Supabase — authentication and user identity
• Amazon Web Services (AWS) — backend infrastructure and data storage
• MongoDB Atlas — database storage
• Apple App Store — app distribution and in-app purchases

7. Children's Privacy

The App is not directed to children under the age of 13. We do not knowingly collect personal information from children under 13. If you become aware that a child has provided us with personal data, please visit our Support page and we will take steps to remove that information.

8. Your Rights

Depending on your location, you may have the right to:

• Access the personal data we hold about you
• Request correction of inaccurate data
• Request deletion of your data
• Object to or restrict certain processing of your data
• Data portability

To exercise any of these rights, please visit our Support page.

9. Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of significant changes by updating the "Last updated" date at the top of this page. Your continued use of the App after changes are posted constitutes your acceptance of the updated policy.

10. Contact Us

If you have questions, concerns, or requests regarding this Privacy Policy, please visit our Support page.