List devices in webrtc

I’m listing the devices of my phone in a ionic 4 app using Angular7 and cordova. Calling navigator.mediaDevices.enumerateDevices() I got all audioinput and videoinput but the labels are empty. I know I have to call to this method when the audio and video permissions are granted and I do that.

Connecting to a webrtc sample through Android browser works but through Android WebView not.

Why the labels are empty? How can i list all devices of my android phone?
Thanks