When the device ( smartphone / tablet ) in connected to the POWERUP FPV, it cannot use the WiFi to connect to the internet at the same time. Different devices use different messages to indicate that your connection to the internet through WiFi is disabled, for example: "No Internet Connection"; "Cannot connect to WiFi" etc, and some devices do not show any message.
You can still use the internet through your mobile network (cellular network).
To improve the video streaming while flying the POWERUP FPV it is recommended to switch your device to "airplane mode". In this case your mobile network is also disabled and you will have no internet connection.