Attendance PWA — Haversine Algorithm
Location-based attendance system using real-time distance calculation
Overview
A web-based Progressive Web App for employee attendance management, using the Haversine formula to calculate GPS-based distance from authorized work locations for real-time check-in validation.
Remote and field employees couldn't use location-lock attendance systems, and the company needed a cross-platform solution that worked on any device without requiring app store installation.
Built a PWA with offline-first design and GPS position verification using the Haversine algorithm on the backend. Implemented geofencing with configurable radius per location, photo verification, and a management dashboard with attendance heatmaps.
Eliminated buddy punching incidents, reduced manual attendance processing from 3 hours/day to fully automated. Deployed across 150+ field employees at 12 different work sites.
