[Swordmaker]

I’ll probably wait until someone has convincingly made a watch which communicates via cell phone, without a separate cell phone.

The Samsung Gear S does that now. . . but you still need a late model Samsung Galaxy phone to pair it with to activate it and install apps. You need a separate phone number for your watch.

[RandallFlagg]

They used to make a Star Trek TOS communicator that used bluetooth with your phone to work like the prop did on the show.