Sales visits Tracking App using NFC

We are looking for a developer or small team to build a simple, reliable NFC-based field activity tracking system for our food-display chillers deployed across multiple locations. Each chiller will have a unique NFC tag attached, and our sales representatives will use a mobile app to scan those tags during field visits. The system should provide real-time visibility into salesperson activity, asset visits, and location verification. Project Scope Mobile Application (Android required, iOS preferred) The mobile app should allow sales representatives to: Tap an NFC tag attached to a chiller Read the NFC tag ID instantly Write/update NFC tags when authorized Register and store every NFC tag against a specific asset/chiller Capture: salesperson identity precise timestamp GPS location Sync data securely to the cloud in real time Queue scans offline and auto-sync when internet becomes available Operate with a simple, fast workflow suitable for field teams NFC Features Required The system must support both: NFC tag reading NFC tag writing/programming Additional NFC requirements: Ability to initialize and assign tags to assets Prevent duplicate asset assignments Maintain full history of each NFC tag Track reassignment or replacement of tags if needed Support common NFC standards compatible with Android devices Web Management Portal We need a cloud-hosted admin portal with secure login and role-based access. Core Functions Chiller / asset registry NFC tag registry and management Salesperson management Visit logging and tracking Real-time activity monitoring GPS map view of visits Date filters and salesperson filters CSV / Excel export Asset Monitoring & Reporting The portal should allow us to monitor each individual asset/chiller and generate reports such as: Total visits per asset Total visits per salesperson Daily / weekly / monthly visit trends Missed or inactive chillers Last visit timestamp per asset Visit frequency ranking GPS verification reports Route/activity history by salesperson Duplicate or suspicious scan detection Heatmap or geographical distribution of visits Scan activity by region/city Tag health / replacement history Dashboard A simple dashboard should display: Active sales reps today Number of visits completed Top visited assets Assets not visited within selected period Recent scan activity Map overview of field operations Technical Expectations Preferred technologies include: Flutter or React Native for mobile Firebase, Supabase, AWS Amplify, or similar backend Lightweight and scalable architecture Secure API and authentication Clean and maintainable source code Developer should provide: Full source code Deployment instructions Database structure/documentation Brief admin and user guide Basic post-deployment support Ideal Experience We are looking for someone with experience in: NFC tooling and tag management Mobile apps with GPS/location tracking Offline-first mobile synchronization Cloud dashboards and reporting systems Asset tracking or field-force automation systems Please include: Suggested tech stack Estimated timeline Similar projects completed Questions or recommendations regarding workflow, NFC structure, or reporting design