Mobile Fuel Inventory & Blending App (Android + iOS, Multi-User) Project Description I am looking for an app developer to build a mobile-first inventory application for fuel trading and blending operations. The app will be used by drivers, supervisors, and the management team, so it must be simple, fast, and practical for daily use. The core functionality includes product setup (diesel, furnace oil, used oil, etc.), tank-wise inventory tracking with multiple tanks per product, inward and outward stock entries, automatic balance updates, and a blending module that calculates total blended quantity and average cost per liter based on input quantities. Drivers should be able to enter delivery quantities and basic details, supervisors should be able to verify entries and manage site-level tank stock, and management should have visibility into overall inventory, blended rates, and summary reports. The app should support user roles and logins, basic reports such as current stock and daily or monthly movement, and the ability to export data to Excel or CSV. The app is required on both Android and Apple iOS, preferably built using a cross-platform framework like Flutter or React Native, with a lightweight cloud backend such as Firebase for data sync. The UI should be very simple, mobile-friendly, and optimized for quick data entry, even on low-end devices. This project is for a basic MVP, not a full ERP system, with a target timeline of 3–5 weeks. Please include your fixed-price quote, technology stack, estimated timeline, and examples of similar mobile apps you have built. Future features like GPS tracking, GST invoicing, and accounting integration may be added later but are not part of this scope.