Demos
Demos
Small interactive pieces, mostly about questions I got curious about outside work. Each runs in your browser and keeps whatever you enter on your device.
Interactive map · Ancient history
Roman News Isochrones
How many days did a message need to cross the Roman Empire? Pick a starting city, a messenger and a season, and the map colours the Empire by travel time. Tap a city to see the fastest route by road and sea. The model is checked against journeys recorded by Cicero, Plutarch, Tacitus and Pliny.
Field app · Birding · The 2012 app, ported 1:1
AndroBird (2012)
In 2012 my brother and I built AndroBird, an Android app for recording bird and amphibian sightings. This is the same app rebuilt for the browser. Point your phone at the bird, estimate the distance, pick the species, and AndroBird places the sighting on the map using GPS and the compass. It covers more than 1,400 species with German names and exports to MiniAvi and CSV. You can install it on a phone and it works offline.
The app is in German, like the original. It works best on a phone with GPS and a compass. On a computer, set the direction by dragging the compass, or long-press the map to add a sighting. Your sightings stay in your browser; only the map tiles are loaded from OpenStreetMap or Esri.
Field app · Birding · 2026 edition
AndroBird 2026
The same idea, rebuilt with what a phone can do in 2026. Raise the phone and the bearing comes from the camera, corrected for magnetic declination. Say or type “3 red kites flying over” and the form fills itself in. It records survey walks with a GPS track, uses the European breeding codes, can blur the nest sites of sensitive species, and exports to eBird, GPX and GeoJSON as well as MiniAvi and CSV.
In English, German and French. On a computer, open the Sightings tab and load the example data, a morning survey walk at Haff Réimech. It keeps its sightings separate from the 2012 version.