Client Background
A rapidly growing financial technology startup launching a peer-to-peer mobile payments wallet and merchant QR-code settlement network across both iOS and Android platforms.
The Challenge
Building financial apps requires zero tolerance for client-side tampering, reverse engineering, or token hijacking on rooted/jailbroken devices:
- Device Diversity: Ensuring uniform 60fps UI performance across low-end Android smartphones as well as flagship iPhones.
- Biometric Security: Securely binding private signing keys to the device’s hardware Secure Enclave or Android Keystore.
- Offline Ledger Resilience: Supporting localized balance caching and offline QR generation without double-spend vulnerabilities.
The Engineering Solution
TheWebSolve architected a cross-platform mobile architecture built on Flutter:
- Hardware Secure Storage: Leveraged native platform channels to interface directly with iOS Keychain and Android KeyStore, ensuring payment keys are never exposed in plaintext RAM.
- Jailbreak & Root Detection: Integrated proactive defensive checks that immediately invalidate sensitive session tokens if device tampering or debugger attachment is detected.
- Optimized Local SQLite Vault: Engineered an encrypted SQLite database that synchronizes with backend microservices via idempotent queues.
Measurable Outcomes
- App Crash Rate: Maintained below 0.01% across 120,000+ monthly active mobile users.
- Biometric Login: Average unlock time dropped to 140ms with zero biometric bypass flaws.
- App Store Approvals: Expedited initial compliance reviews on both Apple App Store and Google Play Store with zero security rejections.
“
TheWebSolve gave us a mobile engineering team that treated biometric security and offline token caching with the same defensive paranoia we expect in banking. The app runs at a fluid 60fps on both iOS and budget Android devices.