Bottom line: The VOCOlinc MistFlow Smart Humidifier offers cool mist, cool colors, and cool controls, thanks to HomeKit. Combined with an extra-large water tank and essential oil diffusing, the MistFlow is the best HomeKit-enabled humidifier around.
Large tank, long runtime
Works as an essential oil diffuser
Color mood lighting
Works with HomeKit, Alexa, Google Assistant
Missing empty alerts
Cool mist only
Requires VOCOlinc app for some features
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Like many, I will admit that I have ignored the health benefits of maintaining healthy humidity levels in the home for many years. Despite knowing that the best humidifiers for your home help keep things like our skin and lips moisturized during the winter and how they aid with respiratory conditions, they have always been relegated to sick days only in my household.
However, I have come around on humidifiers recently, though, thanks to the release of the first HomeKit-enabled option in North America — the VOCOlinc MistFlow Smart Humidifier, which I have been testing in my home for the past few weeks. VOCOlinc's humidifier scratches the new smart home gadget itch nicely, plus with colorful mood lighting, large water tank, essential oil diffusing, and HomeKit, the MistFlow has actually become part of my daily routine.
Misty and moody
VOCOlinc MistFlow Smart Humidifier Review: What I like
The VOCOlinc MistFlow Smart Humidifier sports a clean, two-piece cylindrical design with a translucent, large-capacity water tank. The non-removable water tank holds up to 2.5 liters maximum, and it is easy to fill thanks to a convenient top-fill design which I am fond of. When filled, VOCOlinc states that the humidifier can run up to 30 hours, which I find to be a rather low estimate as I have seen it run for days even at high mist volume settings.
On the front of the humidifier are two capacitive buttons for powering the unit on, adjusting mist and mood light settings, and two small white indicator lights. The humidifier supports five mist volume levels, but on-device controls are limited to cycling between two speeds. Regardless of speed, the MistFlow operates quietly, with your everyday noises easily downing out the humidifier, although you will hear some water noises occasionally.
On the top of the humidifier is a single water droplet-shaped outlet where the cool mist rises out from, and with a generous size, you can easily determine when it is at work. At the maximum level, which is how I keep mine set to at all times, the humidifier pumps out an impressive amount of mist considering its size. VOCOlinc mentions that the humidifier can cover rooms up to 430 square feet in size, and I do not doubt that at all, especially at the max mist volume.
The MistFlow Smart Humidifier's other headline feature is the built-in mood lighting capabilities, which are used every day in my household. The humidifier supports up to 16 million colors and shades of white, just like you see on the best HomeKit light bulbs, plus it supports dimming adjustments great for night time use. The combination of the translucent tank and the LED lighting system looks incredible when filled as the water inside takes on whatever color light is shining through.
Although I could not track down the exact maximum lumen specification for the humidifier, I will say that the light is bright enough to provide a little ambiance in smaller rooms at night. Based on all of the different smart lighting options that I have tested over the years, I would say that the humidifier sits between 120-300 lumens, not overly powerful, but good enough considering it's a secondary feature.
Setting up the MistFlow was quick and easy, thanks to HomeKit compatibility. Just like you get with most HomeKit accessories, the MistFlow is ready to go in minutes by scanning the pairing code located on-device through the Home app, with no account registration or alternate app download required.
The MistFlow connects to 2.4GHz Wi-Fi networks, which has resulted in lightning-fast response times and solid reliability during testing. Lighting adjustments and setting target humidity levels take just a second to take effect, like most Wi-Fi devices. For reliability, I have only come across only one instance of "No Response" status in the Home app so far, which immediately updated and became available without intervention.
Over in the Home app, the MistFlow is exposed as a single accessory with independent controls for the light and humidifier by default. The Home app presents controls for both with a familiar slider where you can make minute adjustments for brightness or target humidity and a set of six preset color options for the mood light which I use often.
Diving into Home app settings for the humidifier portion of the MistFlow reveals current relative humidity levels, determining when the unit runs. While I like how the relative humidity is available for review, the Home app doesn't include the measurement amongst other climate sensors, which is quite odd. Humidity as a trigger for automation with other accessories is also not available, although this isn't unique to the MistFlow humidifier and is a Home app limitation.
To get the most out of the MistFlow, you will need to download the VOCOlinc app, available on iOS and Android. Through the VOCOlinc app, you can access controls for all five mist settings, scheduling, color adjustments, and colorful scenes, complete with customization options. For HomeKit users, the VOCOlinc app offers a HomeKit-only mode that provides these advanced features without an account, which I really appreciate.
Once in the app, VOCOlinc accessories are displayed front and center, each with quick power controls that require just a tap to toggle. As the MistFlow combines lighting with humidification, I like how the app separates controls into two specific sections keeping everything clean and easy to manage. Since I prefer to have the MistFlow set to the highest mist volume, I spend most of my time in the lighting area, where the mood lighting effects are found. I love the "Flow" mood lighting effect, as it offers a gentle transition between a series of colors, and I really like how you can adjust the speed of intervals.
VOCOlinc's LinkWise app is a vital part of the MistFlow Smart Humidifier experience with colorful scenes, schedules, and additional mist output settings.
Apps, alerts, and annoyances
VOCOlinc MistFlow Smart Humidifier Review: What I don't like
Although navigating and making adjustments via VOCOlinc's app is pretty straightforward, I prefer using just one app — the iOS Home app, for all of my smart home needs. Unfortunately, as previously mentioned, some features of the MistFlow are not available outside of VOCOlinc's app, making some adjustments confusing and maintaining specific settings frustrating.
For example, the colorful lighting effects that I usually leave the humidifier on are only available through the VOCOlinc app. This means that any solid color changes that I make through HomeKit/Siri will force me to go back to VOCOlinc's app to set it back to a scene. I would really like to see VOCOlinc take a page out of Nanoleaf's playbook and provide a way to push these scenes over to the Home app, as I don't particularly like having to jump back and forth.
Setting mist output can also be confusing as the Home app only supplies controls for desired humidity and not actual mist levels. For instance, you would think that setting the humidifier to 100% in the Home app would ramp up the device to its highest output automatically, but it doesn't. If it were in the lowest setting previously, it would stay that way. Now, you can make output settings and color scenes available through HomeKit using a third-party app, but again, I prefer just using one app and keeping things as simple as possible.
Rounding out my list of complaints with smart functionality is that the "Empty Alert" option in the VOCOlinc app doesn't appear to be working at this time. During testing, I ran the humidifier until it ran out of water several times, and on each occasion, the app failed to deliver a notification. This isn't really a safety issue as the unit still automatically shuts off when empty, but it would be nice to have this feature working as it would be quite convenient for keeping up on its status.
My only hardware gripes with the MistFlow are that it is limited to cool mist humidification, and its mood lighting won't replace a full-blown accent light. As the name implies, cool mist humidifiers tend to provide a slight chill during operation as there is no heating involved, like with warm mist offerings. You will not notice the temperature difference in most cases, but having warm mist during the winter months would be a nice benefit. Switching over to the mood light, the humidifier is not bright enough to light up an entire room at its peak levels, and color reproduction is less than perfect as I could not get a true red color out of it.
When it comes to smart competition, the VOCOlinc MistFlow doesn't have much currently — especially for HomeKit-enabled options. In fact, VOCOlinc's humidifier is the only game in town for Apple's smart home ecosystem in North America as of now. There is one option — the FlowerBud Aroma Diffuser, which is also from VOCOlinc that is fairly close, but it is tailored to aromatherapy and not humidification.
Compared to the MistFlow Humidifier, the VOCOlinc Aroma Diffuser has a smaller 300 mL water tank, and it retails for around $20 less. Still, the Aroma Diffuser includes the same mood lighting and five adjustable mist levels. The tiny tank allows the Aroma Diffuser to have a sleeker design that fits in better around the home and makes it one of the best travel HomeKit accessories that you can buy today. However, as you might expect, the smaller tank means more refills, and it doesn't come anywhere close to putting out the amount of mist that the larger option is capable of.
Outside of the HomeKit world, popular smart options include the TaoTronics TT-AH019 and the Sierra Modern Home Smart WiFi Diffuser. These humidifiers have similar size tanks as the MistFlow but have drastically different designs, and they only work with Alexa and the Google Assistant for voice control. Without HomeKit support, you cannot control these humidifiers with Siri through your phone or HomePod, and they will not be available for automation with other accessories or with scenes.
Of course, there are plenty of "dumb" humidifier options also available. Some of our current faves include the TaoTronics Top-Fill Hybrid Ultrasonic Humidifier and the Elechomes Warm & Cool Mist Humidifier, both of which have a handy on-device display, physical remotes, and support both warm and cool mist functionality. Speaking of cool mist, our top pick for the best cool mist humidifiers is the Boneco Air-O-Swiss Ultrasonic Humidifier 7147, which has a massive three-gallon tank making it suitable for larger areas than the MistFlow, covering rooms up to 600 square feet.
VOCOlinc MistFlow Smart Humidifier: Should you buy
You should buy this if ...
You want a HomeKit-enabled smart humidifier
The VOCOlinc MistFlow is the only dedicated HomeKit humidifier available on the North American market today. HomeKit allows you to control the desired humidity using just your voice with Siri, and you can incorporate the humidifier into your existing automation and scenes.
You want a humidifier that also works as a diffuser
In addition to humidification, VOCOlinc's MistFlow also functions as an essential oil diffuser. By acting as a diffuser, you can get more out usage of the MistFlow, especially during the warmer months when you may not necessarily need extra humidity in the air.
You want a humidifier that offers basic mood lighting
VOCOlinc's humidifier provides basic mood lighting with the ability to display up to 16 million colors. The MistFlow also supports three customizable scenes that include colorful fades and transitions.
You should not buy this if ...
You want a warm mist smart humidifier
The VOCOlinc MistFlow does not offer warm mist capabilities and is limited to cool mist humidification. If you want a humidifier that will warm up your environment on a cold day, then you will need to look elsewhere.
You only want to use HomeKit for adjustments and settings
While you can use the MistFlow without downloading the VOCOlinc app, some adjustments and settings are not available through HomeKit and the Home app. Color scenes and mist output levels will require you to juggle two apps.
You expect to use the mood light as an alternative to smart accent bulbs and lamps
The mood light in the MistFlow humidifier is a nifty little bonus, but it will not give you the oohs and ahs like the best HomeKit light strips. The onboard light isn't bright enough, and color reproduction is lacking.
Chances are, if you are reading this review, then you most likely are interested in the HomeKit capabilities of the MistFlow. With that being said, if you want a humidifier that works with Apple's ecosystem, then this is your best — and only bet. The MistFlow gets the basics right, and it throws in the essential oil diffuser and colorful mood lighting, which are handy to have around. However, if HomeKit isn't a priority or if you want warm mist capabilities, then the MistFlow is not for you.
Being the first HomeKit humidifier in North America, VOCOlinc certainly could have phoned it in by just providing the basics, and it still would have been a sure hit. However, with the MistFlow, VOCOlinc went above and beyond the norm with colorful mood lighting, essential oil diffusing, high maximum mist volume, and long run time with an extra-large water tank. Mixed with responsive controls, excellent reliability, and of course, HomeKit, and you get not just one of the best smart humidifiers available, but one of the best humidifiers that you can buy today.