Overview
We are seeking an experienced Freelance Mobile App Developer to design, build, and deploy a complete, cross-platform E-Commerce mobile application for both iOS and Android. The primary business objective is to deliver a smooth, performant, and engaging mobile shopping experience that enables customers to seamlessly discover products, complete secure checkout transactions, and track order fulfillment in real time.

This project covers the complete mobile development lifecycle: from translating product catalogs and UI flows into high-quality, responsive screens (Flutter or React Native), connecting backend RESTful APIs and secure payment gateways, to rigorous cross-device QA testing and official store publication on the Google Play Store and Apple App Store.

Scope of Work

Architecture & UI Implementation: Build and configure a production-ready cross-platform mobile application supporting iOS and Android with modern, responsive UI screens including Home Feed, Featured Carousels, Category Navigation, Product Details (PDP), and Wishlist.
E-Commerce Core Features: Implement instant product search, auto-suggestions, and multi-parameter filtering (categories, price ranges, ratings, attributes). Build interactive shopping cart management with real-time total calculation, promo code application, and persistent local storage. Create a streamlined multi-step checkout workflow with shipping address management and payment selection.
User Accounts & Order Tracking: Implement user authentication (email/password, OTP phone login, or social login) with secure token management. Build user profile dashboards, saved delivery addresses, and comprehensive order history. Create real-time order status tracking with timeline status updates from processing to delivery.
Backend Integration & Services: Integrate mobile clients with backend RESTful APIs, endpoints, and database models. Connect online payment gateway SDKs (Credit/Debit Card, Digital Wallets) with end-to-end transaction handling. Configure push notifications (FCM / APNs) for order milestones, promotional announcements, and user alerts.
Testing, Store Deployment & Support: Perform functional, performance, and security testing across multiple screen sizes and OS versions. Handle complete release preparation, code signing, and publishing to Apple App Store and Google Play Store. Provide a dedicated post-launch support and bug-fixing window.

Required Skills
Category: Programming & Tech

Mobile App Development — CrossPlatform Development
Mobile App Development — iOS App Development
Mobile App Development — Android App Development
Software Development — API & Integrations
Mobile App Maintenance — Mobile Store Management
QA & Review — Software Testing

Nice to Have

Proven track record with state management architectures (BLoC, Riverpod, Provider, or Redux).
Hands-on experience integrating regional and global payment gateways (e.g., Paymob, Tap, Stripe, HyperPay).
Familiarity with offline caching, local data persistence (Hive/SQLite), and analytics tools (Firebase Crashlytics, Mixpanel).

Deliverables

Fully functional, well-documented cross-platform source code repository with clean modular architecture and build scripts.
Production-ready release builds (.ipa and .aab / .apk) signed and configured for deployment.
Successful publication and approval on both Google Play Store and Apple App Store.
Technical documentation including API integration guide, build instructions, and environment configuration.
30-day post-launch technical warranty for bug fixes and stability monitoring.

Success Criteria

Android and iOS applications pass Google Play Console and Apple App Store review and publishing guidelines on initial submission without compliance rejections.
Complete checkout and payment flow functions with 100% data integrity and instant confirmation response.
App maintains smooth 60fps rendering, sub-2-second screen transition speeds, and zero unhandled crash exceptions.

Assumptions

Backend API endpoints, database schemas, and product data models are provided or documented for mobile client consumption.
Apple Developer and Google Play developer console credentials will be provided by the client for final publishing.

Estimated Complexity: Medium
Suggested Project Category: Programming & Tech
Suggested Experience Level: Intermediate