T-Mobile introduces video calling for selected models
The carrier's CTO, Neville Ray, said in a message that with T-Mobile video calling, there will be no need to download any apps. Camera icons will appear next to the names of your contacts that are able to accept T-Mobile video calls. If that person has disabled the feature for the moment (use your imagination to guess why), the camera icon will be "greyed out." Ray added that T-Mobile is working with the other carriers to make video calling work across different wireless pipelines.
Current software updates have already enabled the Galaxy S6 edge+ and the Galaxy Note5 to use video calling. Simply go to Settings > About Device > Software Update on either phone. The updates for the Galaxy S6 and Galaxy S6 edge will start rolling out next week.