Greenline Transit

A journey planner with live arrivals and offline tickets, used by 300k riders across the Netherlands.

The challenge

Greenline’s old app crashed at rush hour and tickets disappeared underground. Riders were giving up and queuing at machines again.

What I built

I rebuilt the app in React Native with an offline-first data layer, live arrivals over GTFS-Realtime, and QR tickets that work in tunnels with no signal.

The result

300k riders use the app every month, crash-free sessions sit at 99.8%, and support tickets about tickets fell by 60%.