Works great and has a 1 hour, 3 hour or 5 hour setting. You can also have it go continuously or puff in intervals. It will also oscillate between colors for a nicer nightlight effect. I haven't used the Bluetooth feature and it didn't come with instructions on how to use that, so I can't comment on that function but otherwise I love everything else. The reservoir seems to hold about 5 hours if left on continuously. It will shut off automatically if needed.