Digital Banking App: Serving 15M Customers Securely
End-to-end testing of a digital banking application handling 15M active users with real-time payments, biometric authentication, and regulatory compliance.
Contact UsClient
One of India’s largest private sector banks
The Challenge
The bank was launching a completely rebuilt mobile banking app to replace its aging platform. The app needed to support UPI payments, biometric authentication, mutual fund investments, and credit card management. With 15M active users, any defect could have massive reputational and financial impact.
Our Solution
Our 60-member team executed comprehensive functional, security, performance, and usability testing. We validated biometric authentication across 200+ Android and iOS devices, tested UPI payment flows against NPCI specifications, and performed penetration testing covering OWASP Mobile Top 10 vulnerabilities.
Mobile banking is where financial institutions win or lose customer trust. Every transaction must be instantaneous, every authentication seamless, and every rupee accounted for.
Our device testing lab included 200+ physical devices covering 95% of the Indian smartphone market. We tested across varying network conditions including 2G, 3G, 4G, and WiFi, ensuring the app performed well even on entry-level devices.
Security testing was exhaustive — we conducted static and dynamic analysis, reverse engineering attempts, man-in-the-middle attack simulations, and jailbreak/root detection validation. Every vulnerability was documented, prioritized, and resolved before launch.
The UPI integration required meticulous testing against NPCI’s sandbox environment, validating every edge case from expired VPAs to bank server timeouts.
Key Results
App launched with 99.97% crash-free rate
4.7-star rating on both App Store and Google Play within 3 months
Zero security incidents in first 12 months post-launch
UPI transaction success rate of 99.8%, exceeding industry average
Customer migration from old app completed with 94% adoption rate
Technologies Used
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