Why the end user client can not access the backend service?

The end-user client's app_config.dart backendApiBaseUrl should be set to an URL of the backend that is accessible by the end-user client.

It can be one of the following:

• publicly exposed base URL of the backend service
• if using an emulator on the same machine where the backend service is running -> http://10.0.2.2:8080
• if using a physical device connected to the same Wi-Fi as to which the backend service is connected to -> backend service machine IP address assigned by the router