Quick-Commerce Mobile App Development

I need a Zepto-style quick-commerce application built for both iOS and Android. A shared codebase such as Flutter or React Native is fine, provided each store’s guidelines are fully respected.

Core flow
• Sign-up / login (phone, email, social)
• Dynamic product catalogue with search, filters and real-time pricing
• Cart, checkout and seamless order processing

Critical integrations
• Payment gateway for cards, UPI and wallets
• Live link to our inventory management system (API or webhooks)
• Automatic order dispatch to a third-party delivery partner with status updates returned to the app

Deliverables
1. Pixel-perfect UI that follows modern quick-commerce patterns
2. Secure backend (Node.js, Laravel, Firebase Cloud Functions—open to suggestions) with admin panel for product, price and order management
3. Source code, build instructions, TestFlight / internal testing artefacts and support through App Store & Play Store approval

Acceptance criteria
• A new user can register, browse items, pay and receive confirmation within two minutes on 4 G.
• Inventory levels update instantly after every successful order.
• Delivery partner receives the order payload and returns status updates visible to the user.
• No critical crashes in a 100-device Firebase Test Lab run.

Please share your preferred tech stack, relevant quick-commerce experience and an estimated timeline for the MVP and subsequent milestones.