Privacy Policy
How we collect, use, and protect your information
Last updated: October 6, 2026
Esta Política de Privacidad explica cómo sudokufriends.io ('nosotros', 'nos' o 'nuestro') recopila, utiliza y protege tu información cuando utilizas nuestra plataforma de Sudoku en línea. Utilizamos Google Analytics, Vercel Analytics, PostHog, Firebase Authentication, Firebase Realtime Database, MongoDB y Sentry como parte de nuestro servicio.
Information We Collect
Personal Information
When you create an account, we collect your name, email address, and profile picture (if you sign in with Google). This information is used to personalize your experience and sync your progress across devices.
When you create an account, we set a country on your profile from your IP address. It is public: it appears on your profile and next to your name. You can change or remove it at any time.
Game Data
We collect information about your puzzle progress, completion times, difficulty preferences, and game statistics. This data is used to enhance your gaming experience and provide personalized recommendations.
Analytics Data
We use Google Analytics, Vercel Analytics, PostHog, and Sentry to understand how users interact with our platform and monitor app performance. This includes page views, session duration, device information, error tracking, gameplay events (such as puzzles started and completed, and multiplayer rooms created and joined), and session recordings with form inputs masked. For visitors from the European Economic Area, the United Kingdom, or Switzerland, PostHog runs without cookies or device storage unless you allow our measurement purposes in our consent dialog, and session recordings are not used; other visitors can opt out on our Cookie Preferences page. This data is used to improve our service.
Feedback
When you send feedback (rating an update, rating a lesson, or the Feedback button), we store your answer, optional comment and email, and your player id, together with technical details that help us reproduce problems: the page and game you were on, your language, time zone, browser, operating system, device model where your browser reports it, screen size and display settings. We use this only to fix issues and improve the app.
Technical Information
We automatically collect technical information such as your IP address, browser type, device information, and operating system. This helps us ensure our platform works properly across different devices and browsers.
Third-Party Services
We use the following third-party services to provide and improve our platform: • Analytics Services: Google Analytics, Vercel Analytics, and PostHog help us understand user interactions and improve performance • Authentication & Data: Firebase Authentication and Realtime Database manage user accounts and real-time game features • Data Storage: MongoDB for secure data storage • Error Monitoring: Sentry for application stability and error tracking Each service processes data according to their respective privacy policies and our instructions.
Cookies and Tracking
We use cookies, localStorage, and IndexedDB to enhance your experience, remember your preferences, and analyze website traffic. You can control cookie settings through our Cookie Preferences.
We use cookies, localStorage, and IndexedDB to store your preferences, progress, and consent choices. You can control your preferences at any time.
How We Use Your Information
• Provide and improve our Sudoku gaming service • Personalize your gaming experience • Sync your progress across devices • Analyze usage patterns to improve our platform • Communicate with you about updates and support • Ensure security and prevent fraud
Information Sharing
We do not sell, trade, or rent your personal information to third parties. We may share anonymized, aggregated data for analytics purposes. We use trusted third-party services like Google Analytics, Vercel Analytics, PostHog, Firebase, MongoDB, and Sentry, which have their own privacy policies.
Data Security
We implement appropriate security measures to protect your information. Your data is encrypted in transit and at rest. However, no method of transmission over the internet is 100% secure, and we cannot guarantee absolute security.
Your Rights
• Access your personal information • Update or correct your information • Delete your account and associated data • Export your data • Opt out of analytics tracking • Withdraw consent for data processing
Data Retention
We retain your personal information as long as your account is active or as needed to provide our services. You can request deletion of your account and data at any time.
International Data Transfer
Your information may be transferred to and processed in countries other than your own. Our service providers (Google, Vercel, PostHog, Firebase, MongoDB, Sentry) may process your data in the United States, the European Union, or other countries. PostHog and Sentry store our data in the European Union. We ensure appropriate safeguards are in place for such transfers.
Children's Privacy
Our service is not intended for children under 13. We do not knowingly collect personal information from children under 13. If you become aware that a child has provided us with personal information, please contact us.
Changes to This Policy
We may update this Privacy Policy from time to time. We will notify you of any changes by posting the new policy on this page and updating the 'Last updated' date.
Contact Us
If you have any questions about this Privacy Policy, please contact us through our contact form or email us directly.