Dual-Platform Crypto Wallet & Card

I’m planning to roll out a full-featured crypto wallet that works seamlessly on both iOS and Android. Beyond standard send/receive functionality, the app must include an integrated exchange so users can swap supported coins without leaving the interface, as well as a smooth in-app purchase flow for buying crypto with fiat.

A key differentiator is the payment card element: users should be able to order a virtual or physical card linked to their wallet balance and spend crypto at regular merchant terminals. I already have preliminary agreements with a card-issuing partner; what I need now is the mobile application, the secure back-end, and the card-wallet linkage.

Core requirements you’ll build:
• Native or cross-platform apps for iOS and Android
• Secure key management, biometric login, and encrypted local storage
• Send/receive for major tokens with real-time fee calculation
• Built-in exchange powered by a third-party liquidity API (your recommendation welcome)
• Fiat on-ramp for in-app purchases via credit/debit card
• Card module that syncs balances, handles authorisations, and shows transaction history in-app
• Admin dashboard for KYC, card activation, limits, and user support tools

Acceptance criteria:
• Apps pass App Store and Google Play review
• End-to-end encryption verified in code audit
• Exchange and card transactions settle accurately on test net and main net environments
• On-boarding from install to first card transaction can be completed in under ten minutes by a new user

If you’ve shipped production crypto wallets before—particularly those tied to Visa, Mastercard, or similar programmes—I’d love to see your work.