Privacy Policy
We believe in clarity. This policy explains what data we collect, why we collect it, and how we keep it safe — written in plain language, not legal fog.
April 1, 2026
1. Information We Collect
We collect only what is necessary to operate the platform: • Account information — your name, email address, and profile picture provided through Google OAuth sign-in. • Subscription data — payment status and plan tier, managed through Stripe. We never store your credit card number or full payment details on our servers. • Usage data — pages visited, features used, and session duration to improve the learning experience. • Technical data — browser type, device type, and IP address for security and performance purposes.
2. How We Use Your Information
Your data serves three purposes: • Providing the service — authenticating your account, managing your subscription, and saving your progress across sessions. • Improving the platform — understanding which lessons, simulations, and tools are most useful so we can focus development where it matters. • Communication — sending account-related emails such as subscription confirmations or important service updates. We do not send marketing emails unless you opt in.
3. Authentication
We use Supabase as our authentication provider. When you sign in with Google, we request the openid, profile, and email OAuth scopes. This gives us access to your name, email address, and profile picture. Your Google password is never shared with us. Authentication sessions are maintained through secure, HTTP-only cookies. This application's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.
4. Payments
All payment processing is handled by Stripe. When you subscribe, your payment information is sent directly to Stripe's secure servers — it never touches ours. We receive only a confirmation of your subscription status, plan type, and Stripe customer ID. Stripe's privacy policy governs how your payment data is handled on their end.
5. Cookies
We use essential cookies to maintain your authentication session and remember your preferences. These are strictly functional — we do not use advertising or tracking cookies. Without these cookies, core features like staying signed in would not work.
6. Third-Party Services
We integrate with the following services, each governed by their own privacy policies: • Google OAuth — for authentication. • Supabase — for database and authentication infrastructure. • Stripe — for payment processing. • Vercel — for hosting and content delivery. We do not sell, rent, or share your personal information with any third party for advertising or marketing purposes. Your data may be stored on servers operated by Supabase and Vercel in various regions. By using the platform, you consent to this transfer. All data is encrypted in transit using TLS and at rest where supported by our infrastructure providers. Authentication tokens are stored in secure, HTTP-only cookies.
7. Data Retention
We retain your account data for as long as your account is active. If you delete your account, we will remove your personal data within 30 days, except where we are legally required to retain it. Anonymized usage analytics may be retained indefinitely to improve the platform.
8. Your Rights
Depending on your jurisdiction, you may have the right to: • Access the personal data we hold about you. • Request correction of inaccurate data. • Request deletion of your data. • Export your data in a portable format. • Withdraw consent for data processing. To delete your account and all associated data, email contact@quantumcircuitsimulator.com with the subject line "Delete My Account". Include the email address associated with your account. We will process your request and permanently remove your data within 30 days. To exercise any other rights, contact us at the same address.
9. Children's Privacy
This platform is designed as an educational tool and is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal data, please contact us and we will promptly delete it.
10. Changes to This Policy
We may update this policy as our platform evolves. When we make material changes, we will notify you by updating the effective date at the top of this page and, for significant changes, by email or an in-app notice.
11. Contact
If you have questions about this privacy policy or how your data is handled, reach out to us at: contact@quantumcircuitsimulator.com