Only employees of the DB Group can activate this app with a voucher code. With the app you get to know the DB's railway signals and can read the contents of the signal book.
You can only receive the voucher code for activating the app from your employer. Voucher codes can be ordered here: www.db-training.de/signalapp
If you are not a DB employee, we recommend our "DB Signals" app. The content and functionality of the app are identical.