Flutter Grocery Delivery App

I need a production-ready Flutter app that lets shoppers place grocery orders from a 10 000-item catalogue exposed through my existing REST API. The app’s core job is a seamless ordering flow—browsing and search endpoints are already in place, but the emphasis is on adding items to cart, confirming quantities, and submitting the order.

Customers must authenticate only with a phone-number OTP; no email or social login is required at this stage. At checkout the sole payment option will be Cash on Delivery, so the UI can stay lean and skip card or wallet integrations for now while still leaving the codebase flexible for future gateways.

The API returns structured product data, stock status, and pricing. You’ll handle:

• Consuming and paginating large lists efficiently
• Managing cart state locally until checkout
• Sending create-order, cancel, and reorder calls
• Displaying real-time order status updates pushed from the API

Clean architecture, proper state management, and concise documentation are essential because my in-house team will maintain the code after launch. Once delivered I expect the full Flutter project, commented source, build instructions, and a short hand-over call to walk through the structure and any third-party packages you introduced.