The data backbone behind the Trackser app. Real-time train positions for the entire network — processed server-side, served globally.
Trackser Live is the server-side infrastructure that powers the Trackser app. Rather than having the app consume raw TfL feeds directly, Trackser Live fetches, merges, cleanses, and enriches train data centrally — then serves compact snapshots to the app. The result is a faster, lighter, and more accurate experience for users, with considerably less on-device processing.
It's built on Cloudflare Workers and R2, with one Durable Object per line handling all the per-line state. Data comes from TfL's TrackerNet feeds — the same granular source used in real-time train control — enriched with direction inference, stall detection, Metropolitan line timetable data, journey tracking, and more.
All 11 Underground lines, serving live train positions for the Trackser app on Android, iOS, and web. The app never touches TfL directly.
Direction inference, stall detection, reformation tracking, Met stopping patterns, destination cleansing — all done before data reaches the device.
Every snapshot is archived. Full-resolution data for 14 days, downsampled from 15–28 days, cold storage beyond that. Journey records kept per railway day.
Currently internal — the API serves the Trackser app only. If there's demand for external access, we'd consider it. Get in touch if you have a use case.
Questions about Trackser Live, data access, or technical enquiries:
support@curiosity175.co.uk