Project Title: Hybrid Flutter WebView App for Shopify Store (Custom Auth & Razorpay Integration) Project Description: I am looking for an experienced Flutter developer to build a high-performance Hybrid Android App for my Shopify-based bookstore (books.ataka.in). The store uses a custom Liquid theme with specialized collection logic. The goal is to wrap the existing Shopify store into a native Android experience while solving specific authentication and payment hurdles common in the Indian e-commerce landscape. Key Requirements: Core Architecture: Flutter-based WebView wrapper. The app must feel native with a custom splash screen, native loading indicators, and "Pull-to-Refresh" functionality. Custom Authentication: I have removed standard Shopify sign-in. You must implement OTPless (WhatsApp Login) as the primary authentication method. The app needs to bridge the WhatsApp login state back to the Shopify session. Payment Gateway Fix: Integration of Razorpay Standard SDK. You must ensure that "UPI Intent" (PhonePe, GPay, Paytm) works flawlessly. The app must correctly handle external URL redirects to payment apps without getting stuck in the WebView. JavaScript Injection/Bridge: The app needs to handle specific JavaScript events from my Shopify theme (e.g., triggering a native Android share sheet or custom "Add to Cart" notifications). Push Notifications: Integration with Firebase Cloud Messaging (FCM) for marketing and order updates. Performance: Implement User-Agent spoofing to ensure the mobile-responsive theme loads the "App-specific" version of our custom collection view (which handles 500+ products). Technical Stack: Framework: Flutter (preferred) or React Native. Backend: Shopify Admin/Storefront API. Payment: Razorpay. Auth: OTPless (WhatsApp). Deliverables: Source code for the Android App. Configured Firebase and OTPless environments. Signed APK and App Bundle (AAB) for Play Store release. Note to Freelancers: Please mention if you have specifically handled the Razorpay UPI Intent issue in previous WebView projects. This is a critical requirement.