It only works with batteries; when I connect it to the power supply, it doesn't work.
There is a bit of noise when it's in operation, but it's effective and that's good.
For those living in Korea, you don't need to worry about the plug type.
First of all, the included adapter is a 100~240v universal voltage adapter, but
Please note that you can use any charger as long as it has a common output of 5V 1A or higher for USB-A or Type-C smartphone chargers. It seems like you just need to choose the color you want.
The app integration is also good.
These diffusers are sleek, easy to load up, large in capacity. They dont really permeate the household as advertised but they do "ok". The advert says they cover 5k square feet, but i only have 900 upstairs and 800 downstairs...and have placed one each on each floor. They dont really stand out in terms of lasting fragrance...but i still think they are ok, and less mess than my febreze, etc. I am still glad i got them...even though i have now had to buy a poopload of essential oils to go w/ them. Further than i was.
The only issue i had was that the app is a little difficult to use. But i got through it.
It arrived very quickly, I haven't tried it yet, I will update once I do.