As described in How to scan or read Window.ID Tag | Window ID you have three options to read and scan the Window.ID Tag.

With the new changes, the camera preview is now not displayed when opening the App. To activate the camera for scanning the Window.ID Tag, you need to click on the "Start Scan" button.

And if you want to switch between cameras there is now a special option for this - the "Switch Camera" button on the top bar.

On the "Switch Camera" tab, you will see all the possible cameras that your device has. To see a preview of each camera, you need to click on the "Start Preview" button at the bottom. After selecting the camera you want, press the "Back" button at the bottom of the screen to return to the scanning process.

Release notes - v3.7.1