The amount of people in the comments who don't know that aroma therapy is a thing and oil diffusers aren't only or even primarily used for homes that "smell", is too. damn. high. Those diffusers can also be used without essential oils and essentially become...you guessed it: humidifiers.
I've been occasionally looking for a smart diffuser, because my cluttered brain routinely forgets to turn them off. But unfortunately the selection isn't only small, they also all look... let's call it ugly.