In addition to fog, the upper part can also highlight color. But that is only seen in the dark.
The manual is in English only, in principle, the diffuser can be operated but easy. There are only 2 buttons, the top is on / off, the lower for the light function. In continuous operation of the diffuser runs approx. 3 hours until the water has run out, some of it still remains left. 2-3 drops of fragrance oil are enough. If you press the On / Off button several times the unit will only briefly and then turns off after a few minutes.
The handling and the opening and closing of the diffuser is a bit awkward, but I think it's still simpler and more reliable than the shells with tealight. By the fan, the device does not react silently, for the bedroom, it is not more appropriate.