Live Map of the London Underground

Original Article ↗ Hacker News Discussion ↗

Overall Reception & Aesthetics

  • Widely praised as “beautiful”, “hypnotic”, and fun to watch for long stretches.
  • Users like that it uses a real geographic map rather than the usual schematic diagram.
  • The 3D basemap (likely MapTiler + OSM) impresses people; some can even spot their own buildings.

Data Source & TfL API Discussion

  • The app uses live TfL tube data, which several commenters describe as painful and inconsistent.
  • Issues mentioned:
    • Different spellings of stations and free‑text status messages.
    • Multiple backends (arrivals boards vs TrackerNet) giving inconsistent or lagged data.
    • Load-balancing sometimes returning older data than previous calls.
  • Some argue this is “perfectly fine” for human‑oriented arrival boards but bad as a general API.
  • A few suggest that modern AI/LLMs are actually good at normalising this messy data.

Coverage, Lines, and Classification

  • Repeated questions about missing lines: Elizabeth line, Waterloo & City, Hammersmith & City, DLR.
  • Explanations given: some of these are not officially “Underground” lines or are present but invisible/hard to see, with tooltips only.
  • One comment notes an unbuilt Met line extension still appears.

Bugs, Lag, and UX Feedback

  • Observed issues:
    • Around ~1 minute lag compared to being physically on a train; trains sometimes “disappear”, especially when stopped or at display edges.
    • Overlay not perfectly locked to the map when panning/zooming; zoom/pan described as “broken” for some.
    • Times displayed in UTC instead of local time.
    • Trains drawn above 3D buildings feels visually odd; some want them to appear “underground” or with depth information.
    • Single polyline where multiple lines share track is confusing; overlapping trains in opposite directions are hard to read.
  • Suggested improvements: direction arrows, clearer station rendering, brighter trains vs darker stations, different icons (dots/arrows/boxes), a “reset view” button, open‑sourcing for contributions.

Comparisons & Spin‑off Ideas

  • Many links to similar real‑time transit visualisations (Tokyo, Vienna, Berlin, Poland, Portland, UK mainline rail).
  • Several note it’s more “pretty than practical” but still valuable for gauging when to leave home.
  • Inspired ideas include games using real‑time transit data, richer city‑scale 3D simulations, and visualising crowd movement.