Levoit Classic 300S Ultrasonic Smart Humidifier is a must for large rooms. The water tank has great capacity and the mist has a very high reach when set up on the highest level. The 6-liter humidifier provides up to 60 hours of continuous mist when on the lowest setting, it has 4 mist level settings, aromatherapy drawer on the side, and an optional night light that can be turned on and off. Our sleep quality has improved and even our skin isn’t so tight and dry. This humidifier is by far the most powerful and effective I have ever used. My favorite part about it is that you don’t need to add essential oils directly to the water - it has a separate little drawer for that. I haven’t used it with an app yet, but it looks like it’s very easy to use. I highly recommend this humidifier.