A few days ago Apple published a new patent for voice communication solutions. They can be used in future models of headphones of this company.
The Apple patent describes headphones equipped with a feature that allows users who are close to each other to make direct voice calls quickly and conveniently. The advantages of this solution are to simplify the process of making contact and minimize delays during sound transmission. An example of practical application of this function is given for conversations in noisy environments and while watching a movie with earphones on.
Of course it is important to remember that Apple often patents various solutions "just in case". So just getting a patent doesn't guarantee that this feature will actually appear in any future headset model.