You seem rather certain of what this thing that you have not seen is not. :) Or is, for that matter.
To my mind, there is a vast need for heating water and air, for building heating, for industrial heating, for pre-heating of water for boilers and the like. So, if this thing that we know little of is really "just a water heater", that is no small thing.
That's if those millions of units that will be manufactured either in one place of another are ever seen by anyone.
So at this point calling it even a water heater is being generous.