I already run a full-featured billing platform on the MERN stack and now need a lightweight companion app built with React Native that talks to my existing REST endpoints. The scope is intentionally tight—three screens that mirror key workflows from the web app. Inventory Screen • View and manage stock levels in real time • Add or remove items on the fly • Track item categories for quick filtering and search Invoice Screen • Create brand-new invoices • Pull up and edit any existing invoice • Trigger invoice dispatch by email directly from the device Report Screen • Generate sales reports • Generate inventory reports • Let users export any report as a PDF they can share immediately I will hand over the full API documentation, sample payloads and Postman collection so you can focus entirely on the mobile side. The UI can stay native to React Native components; feel free to layer in Redux Toolkit or Context if that speeds state management. Final deliverables are: 1. Complete, well-structured React Native source code (iOS & Android ready) 2. Build instructions plus a short README explaining any environment variables and install steps 3. A release-mode APK or TestFlight build to confirm everything runs smoothly against my staging server Clean code, concise commits and a short Loom walkthrough will make sign-off quick and painless.