I need an end-to-end grocery delivery application built for both iOS and Android. The core features are straightforward: a secure payment gateway, real-time location tracking so customers can watch their order move on the map, and an in-app customer support channel that lets users reach help without leaving the app. The flow is classic: users browse groceries, add items to their cart, pay, and then track their delivery until it arrives. I’m open to whichever tech stack you feel gives the best balance of performance and speed to market—native Swift/Kotlin or a cross-platform framework such as Flutter or React Native are both fine as long as the final result meets store guidelines and runs smoothly on current devices. Deliverables • Production-ready iOS and Android apps with full source code • Backend/API with integrated payment gateway (credit/debit card at minimum; ability to extend to others later) • GPS tracking module tied into the order timeline • In-app customer support (chat or ticket system) • Deployment to App Store and Google Play, including test builds and store assets • Basic technical documentation covering setup, environment, and key modules Acceptance criteria 1. A user can register, browse products, place an order, pay, and receive real-time tracking updates without crashes or noticeable lag. 2. Payment transactions are processed through the integrated gateway with confirmation screens and error handling. 3. Customer support messages reach the backend and return responses in-app. 4. Apps pass App Store and Google Play review on first submission (barring policy changes outside anyone’s control). If something in my outline needs clarification, let me know early so we can lock the scope before development begins.