AirServer does not currently support streaming from within the YouTube app, using the built-in Google Cast button, on Android devices.

To work around this limitation, it is possible to mirror the entire phone's screen using the AirServer Connect application and opening the YouTube app afterwards.

Using iOS capable devices, it is possible to use AirPlay within the YouTube app, rather than Google Cast.

We hope to find a way to support direct streaming from within the YouTube app to AirServer in the future.