I am looking for an expert developer or agency to build a high-performance E-commerce Website and Mobile App (iOS & Android) for my helmet business. The core requirement is a seamless, real-time integration with Zoho Books. I currently manage over 5,000 products in Zoho Books and want this data to serve as the single source of truth for both the web and mobile platforms. Key Requirements Unified Database: Direct integration with Zoho Books/Inventory API. Changes in stock, pricing, or product details in Zoho must reflect instantly on the website and app. Scalability: The system must efficiently handle a catalog of 5,000+ SKUs with high-resolution images and variations (size, color, etc.). Web Development: A modern, SEO-optimized, and fast-loading e-commerce site. Mobile App: Native or Cross-platform (Flutter/React Native) apps that sync perfectly with the web store. Order Management: Orders placed on the app or web must automatically generate Sales Orders/Invoices in Zoho Books and update inventory levels. User Features: Customer login, order tracking, payment gateway integration, and push notifications for the app. Technical Preferences Backend: Node.js, Python, or PHP (capable of handling Zoho OAuth2.0 and API rate limits). Frontend: React.js, Vue.js, or similar for Web. Mobile: Flutter or React Native for a single codebase. Database: Use of a middleware database (like PostgreSQL or Firebase) to cache Zoho data for faster performance while keeping it synced. Deliverables Fully functional E-commerce Website. Android & iOS Apps published to stores. Admin panel for minor content management (not handled by Zoho). Complete documentation for API mapping. Information for Bidders Please provide examples of previous Zoho API integrations you have completed. Proposals without specific mention of Zoho experience will not be considered.