This falls into the category of “harder than it sounds,” but an Israeli company at Mobile World Congress is demonstrating a functional VoIP stack running on a generic smartwatch.
Business phone systems that used to be handled by PBXs or Centrex systems have mostly migrated to Voice over IP systems, putting voice communication on corporate data networks instead of more expensive voice wiring. That’s why Cisco desk phones have replaced the old Western Electric telephones (and are today being themselves replaced by “softphones” that run on headset-equipped PCs).
N-sip is showing a technology demo where they’ve put a small VoIP app on a generic Chinese smartwatch. The application: put a fully functional corporate phone on an Android watch.
It’s a demo, not a product, but it does work (which is more than one can say for many tech demos). CEO Nahum Nir showed a call going to another wirelessly connected device as well as a cell phone on a GSM network.
Voice quality wasn’t much to speak of, but acceptable given that it was on a noisy trade show floor and featured a guy on a watch talking to another guy on a watch, and a guy on a watch talking on an Israeli cell phone in Spain.