📱 Mobile App
GPS Tracking (Google Maps API)
Activity Recognition (Walking, Driving, Bus)
Consent & “Nudge” Input

⚙ Backend API Layer
Secure REST API (Firebase Functions / Node.js)
Data Validation
Privacy & Encryption

🗄 Cloud Database
Firebase Firestore / PostgreSQL
Stores trip chains, co-traveler info
Anonymized data models

💻 NATPAC Research Team
Query & visualize trip datasets
Export reports for planning
Real-time analytics