Privacy Policy

Sentence Lab ("we", "our", or "us") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, and safeguard your information when you use our Spanish learning application.

1. Information We Collect

Account Information

When you create an account, we collect:

• Email address
• Name (optional)
• Password (encrypted)

Learning Data

To provide personalized learning, we collect:

• Practice history and progress
• Exercise answers and accuracy rates
• Vocabulary and verb lookups
• Custom sentences and vocabulary you create
• Session length and frequency
• Streak and daily goal data

Payment Information

If you subscribe to Premium, payment processing is handled securely by third parties. On the web, payments are processed by Stripe. On iOS and Android, payments are processed through Apple App Store or Google Play (managed via RevenueCat). We do not store your credit card or payment details. We receive only:

• Subscription status
• Billing cycle dates
• Payment provider customer ID (Stripe or RevenueCat)

Automatically Collected Information

We automatically collect certain information when you use Sentence Lab:

• Device type and browser
• IP address (for security purposes)
• General location (country/region)
• Usage patterns and feature interactions

2. How We Use Your Information

We use your information to:

• Provide and personalize the learning experience
• Track your progress and implement spaced repetition
• Send practice reminders (if enabled)
• Process payments and manage subscriptions
• Improve our content and features
• Respond to support requests
• Prevent fraud and abuse

3. Information Sharing

We do not sell, rent, or trade your personal information. We do not share your data with third parties for advertising, marketing, or tracking purposes. We only share data with service providers who help us operate the app:

• Supabase: Database and authentication provider
• Stripe: Payment processing (web)
• RevenueCat: In-app purchase and subscription management (iOS/Android)
• Resend: Email delivery (for reminders and notifications)
• Vercel: Hosting provider

These providers are contractually obligated to protect your data and use it only for the services they provide to us.

Mobile apps: Our iOS and Android apps do not contain advertising SDKs or analytics tools that track you across other apps or websites. We do not sell or share your data for advertising purposes.

Website: Our website uses Google Ads and Microsoft Advertising to measure the effectiveness of our advertising campaigns. These services may use cookies to track conversions and enable remarketing. You can opt out of personalized advertising through your browser settings or by visiting Google Ads Settings or Microsoft Privacy Settings.

4. Data Retention

We retain your data as long as your account is active. If you delete your account:

• Your personal information is deleted within 30 days
• Learning progress and history are permanently removed
• Payment records may be retained as required by law

5. Your Rights

You have the right to:

• Access: Request a copy of your data
• Correct: Update inaccurate information
• Delete: Request deletion of your account and data
• Export: Download your learning data
• Opt-out: Disable email notifications in settings

To exercise these rights, contact us at privacy@sentencelab.app

6. Security

We implement industry-standard security measures including:

• Encryption in transit (HTTPS/TLS)
• Encrypted password storage
• Row-level security for database access
• Regular security audits

7. Cookies

We use essential cookies on our website and apps for:

• Authentication and session management
• Remembering your preferences

Website only: We also use advertising cookies from Google Ads and Microsoft Advertising to measure ad performance and enable remarketing. These cookies help us understand how users find our website through ads. You can manage cookie preferences in your browser settings.

Mobile apps: Our iOS and Android apps do not use advertising or tracking cookies.

8. Children's Privacy

Sentence Lab is designed to be suitable for users of all ages. We do not knowingly collect personal information from children under 13 without parental consent. If you are a parent or guardian and believe your child has provided us with personal information without your consent, please contact us at privacy@sentencelab.app and we will delete that information.

9. International Users

Your data may be processed in the United States. By using Sentence Lab, you consent to the transfer of your data to the US, which may have different data protection laws than your country.

10. Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of significant changes via email or a notice on our website. Your continued use of Sentence Lab after changes constitutes acceptance of the updated policy.

11. Contact Us

If you have questions about this Privacy Policy or our practices, contact us at:

Email: privacy@sentencelab.app