With the "bw tariff CHECK" app, electronically issued tickets (barcodes and chip cards) of the bw tariff can be checked for their authenticity.
The bw tarif is published by bw tarif GmbH.

To use the app, registration at the local transport company Baden-Württemberg (NVBW) is necessary.

The control is carried out according to the rules of the VDV core application and also includes the writing of transaction data to the chip card and the forwarding of the generated control evidence.
Blocked driving authorizations can be detected via the KOSE procedure and locked when an online connection is established.
A validity check is carried out via the control module of the Fraunhofer Institute for Transportation and Infrastructure Systems.