Trains are represented as arrows, of which the overlaying colored circle denotes an estimation of the actual delay. The map can be explored in a “live-mode”, revealing all current delayed trains, or in an “historic mode”, for instance by dragging (or selecting within) the timeline at the top. A Play-button then highlights the relative movement of the trains as they are traveling, or traveled so far, through Germany. In addition, each train on the map can be selected to display more detailed information (such as the official reasons for the delay, for example).
A separate query interface allows discovering the most delayed trains in a certain period of time, by train station, or by the train number. Resulting trains can then be selected from the result list to be highlighted on the map.
An dedicated, open API to access the actual delay data is in preparation.
Source: Information Aesthetics