The DB had in the past the "Zugradar" available for PC or as in App, but it turned down in 2018. It was GPS or timetable based, linked with the current information in the DB Navigator-App.
Nowadays there are some other websites online for the DB, but none official:
https://www.zugverfolgung.com/db-deutsche-bahn
https://www.zugfinder.net/de/livemap-europa
You may just use Google for some websites.
In Sweden (my home country) the drivers have iPad / tablet apps called "Green Speed" which sees the trains in front of the driven train, keeps the driven trains GPS location and also has the timetable. From that it calculates a "green speed" so that the train doesn't have to keep Vmax but can coast / keep a lower speed for environmental / economical benefits.
A very useful idea, but in Germany a comparable system does not exist (if I recommend correctly). There are only the dispatchers who may advice the drivers and let them know if there is an slow train in front or something.