Keep study access free
Support C-T-ZEN
C-T-ZEN is free for everyone. If the app helps you or someone you care about, you can make an optional one-time contribution.
Optional one-time support
Stripe suggests $5, and the minimum amount is $2. Stripe may show another currency or eligible payment methods based on your location and device.
Continue to secure paymentWhat your support helps fund
Reliable accessHosting, maintenance, and continued PWA availability.
Current materialsReviewing official USCIS publications and maintaining question banks.
Better study toolsAccessibility, performance, and practical improvements to the trainer.
Support never unlocks paid features or preferential service. The complete trainer remains available without payment.
Important payment terms
- Your contribution is voluntary and provides no goods, services, premium access, or other benefit.
- C-T-ZEN is operated by an individual and is not a charitable organization.
- The payment is not a tax-deductible charitable contribution.
- Support payments are final and non-refundable except where a refund is required by law.
Payment questions can be sent to iam@c-t-zen.com. Do not email card numbers or other payment credentials.