Then it would logically follow that smart watches would be called...
microphones.
I'm liking this!
Say hello to the gigaphone. 
What about virtual reality headsets? Facephones?
Those are eyephones
Yeah, that makes more sense.
Except the actual phone part.
The voice chat app?
pretty sure my son with an android tablet and my daughter with a iPad can both still make phone calls lol. They are literally megaphones.
There are VoIP options, sure, but not the actual phone bands.
I'm pretty sure you can get cell data on iPads now, it's pretty interesting that you can't make calls with them even when they have sim cards (or eSim)
A quick search says they can only do wifi calling by relaying your iPhone to your iPad
For all phones there is sim card ability(afaik) Only half of the tablets have that
Apart from megaphones already having that name.
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