Mobile Payment Integration: A Complete Developer Guide

Payment Gateway Selection

Choosing the right payment gateway depends on your target market and business model. Razorpay is the leading choice for Indian apps with support for UPI, cards, net banking, wallets, and EMI — their mobile SDKs handle the entire payment flow with a polished native UI. Stripe provides the best developer experience for global payments with support for 135+ currencies, subscription billing, and advanced fraud detection. For in-app purchases of digital goods on iOS, you must use Apple's StoreKit — this is required by App Store policies and Apple takes a 15-30% commission.

Security and Compliance

Payment security is non-negotiable. Never process or store card numbers in your application — use the payment gateway's SDK to tokenize card data on their servers. Implement 3D Secure authentication for card payments to shift liability for fraudulent transactions. Use certificate pinning to prevent man-in-the-middle attacks on payment API calls. Validate payment status on your server by checking with the payment gateway API — never trust the mobile client's payment success callback alone. Log all payment events for audit trails and dispute resolution.

• Card tokenization: Let payment SDKs handle card data so you never touch raw numbers
• 3D Secure: Add authentication step for card payments to reduce fraud liability
• Server-side verification: Always confirm payment status from your backend API
• Receipt validation: Verify in-app purchase receipts with Apple and Google servers

Partner with Apex Byte

At Apex Byte, we turn complex technical challenges into practical, scalable solutions. Our team brings deep expertise across modern technology stacks and a delivery-first mindset that ensures your project ships on time and on budget. Whether you are building from scratch or modernizing an existing system, we are ready to help. Contact us today for a free consultation.