Targeting smartphones seems like a highly realistic way to make something like this work. The average westerner has like three of them lying around in desk draw

Targeting smartphones seems like a highly realistic way to make something like this work. The average westerner has like three of them lying around in desk drawers and they already have a number of useful peripherals attached. It is much less obvious, especially to the layman, how to turn the microcontroller in the coffee machine into something like a useful gate control device.