Review on LEVOIT Top Fill Cool Mist Ultrasonic Humidifiers for Bedroom with Essential Oils, Smart Control for Baby Nursery Kids and Plants Indoor, Quiet and Easy to Clean, BPA Free, 3L Capacity, White by Jaie Bobin

Unpacked and assembled. Humidity was 45% immediately. Good. Then it started to grow rapidly. The humidity in my house is now around 40% and a separate hygrometer reports 34% and the humidity reported by the 200S goes up to 69%? Without the app, you can set the device to "low" or "high" humidity or "auto". In automatic mode, the humidity is kept within 40-50%. There is no clear indication of low/high settings. But I suspect that a high setting ignores the actual humidity that is being reported. You can set the "automatic" humidity setting via the app. 45% is the default value, trying to keep +/-5%. As I type this, the reported humidity has risen to 74% while the hygrometer reads 34% and no fog is forming. The next day, the humidifier and hygrometer were close enough that I could trust the humidifier. So I think I'll keep it. Although I'm never 100% sure. I bought this to keep my office at around 49% RH for my guitars and so far it does the job based on the hygrometer in the guitar (that's 3 different readings). My only complaint is the in-app ads. I don't have to worry about advertising a product I've paid for.