Area Target Project does not even start Vuforia Camera

Hallo,

I am trying to create a area target application. I scanned the area, followed along the official Vuforia Area Target documentations and tutorials. The area target is shown in unity and I can move around in the simulator mode. I placed some cubes to test if the area is recognized.

When I build the application now and start the app, there is not even the vuforia Free trial text at the bottom, just my normal camera, which led me to the idea that the vuforia camera mode does not even start. Any idea why that could happen?