Offline-ready GPS Field Capture (PWA)

A water utility's field team was recording household connections on paper and phone photos. Data got lost or duplicated and took days to reach the office.

An offline-first web app (PWA) for technicians: pick a point type (registry box, discharge, manhole, business, alert), aim the crosshair and save. Points are queued on the phone and sync automatically when the signal returns. Map areas can be saved for offline use, and every point is grouped into a workday for review.

Used daily by 10 field technicians

35,000+ GPS points registered (homes, registry boxes and connections)

Works without signal: nothing is lost when the connection drops

Stack: React, Vite, Service Worker, IndexedDB, Leaflet, Node.js / Express, MySQL, Railway.