I need a developer who can embed a secure, fully compliant payment flow inside my existing iOS app. The current Swift-based codebase is stable; what’s missing is the checkout layer that lets users pay seamlessly without leaving the application. Here’s what I expect: • Selection and configuration of a reliable online payment gateway (Stripe, PayPal, or your recommended option) that supports cards and Apple Pay. • Clean Swift implementation of the SDK, including tokenisation, 3-D Secure, and error handling. • A simple UI that fits my app’s look—cart review, card entry, Apple Pay sheet, success/failure screens. • Server-side hooks or webhooks (Node.js already running) so transactions, refunds, and receipts are logged correctly. • End-to-end testing in TestFlight and guidance to pass App Store review. I’ll provide the current Xcode project, API keys, and sandbox credentials. Deliverables are the updated source code, basic technical notes, and a quick call to walk me through deployment.