Bottom line: Kyvol's Cybovac S31 packs in tons of high-end features like LiDAR navigation, mopping, and a self-empty system for less than its flashier competitors. Combined with powerful suction, excellent battery life, and smart app controls, the S31 is a perfect choice for keeping your home nice and tidy.
Long battery life
Virtual boundaries and room cleaning
App setup, vague messages
Light mopping only
Lacks Siri voice controls
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Robot vacuums are an incredibly convenient way to keep our homes nice and clean without having to lift a finger. However, as convenient as they are, robot vacs come with their own set of annoyances like small collection bins that you have to empty manually and navigation problems — especially on older models. The latest round of robot vacuums has solved some of these with advanced Light Detection and Ranging Navigation (LiDAR) laser navigation systems and self-emptying collection bins. Still, they can be quite expensive, with popular models reaching as high as $1,000.
That is where the Kyvol Cybovac S31 comes in. While the company may not be a household name, Kyvol's smart vac combines the latest and greatest tech — along with mopping capabilities, with an affordable price tag that makes convenient cleaning accessible to all. Of course, actual cleaning performance is the most critical aspect to consider with robot vacuums, so how does a feature-packed $500 vacuum stack-up? Let's find out.
It does it all
Kyvol Cybovac S31 Robot Vacuum review: What I like
Setting up the Kyvol S31 is straightforward as it ships with all of the essentials installed on both the vac and the charging base inside the box. In addition to the main components, the S31 comes with tons of extras, including a snap-on water tank, replacement self-empty system bags, plenty of mopping pads, remote control, replacement air filters, and replacement side brushes. To keep things brief, aside from self-emptying and mopping, hardware highlights on the S31 include 3,000PA suction power with four adjustable speeds, a 5,200 mAh battery, a 500ml dust collection bin, 110ml water tank, two side brushes, and LiDAR navigation.
Since my home consists of multiple floor surfaces, including carpet, rugs, tile, and laminate, I can test pretty much every performance scenario that a robot vacuum would come across in a typical home — except for stairs. For the most part, the vacuum's suction is good at picking up smaller pieces of your everyday debris like paper, hair, string, and crumbs on softer surfaces. I have seen some issues with the side brushes flinging debris around while on solid surfaces, but the vac usually these pieces up during a subsequent pass.
The S31 has no trouble with the various transitions and thresholds in my home, and its low profile allows it to get to spaces that generally go months without vacuuming, like under a dresser. As the S31 is the first vacuum that I have tested with LiDAR, I am particularly impressed by its smooth navigation around the home and its mapping capabilities. The LiDAR navigation system projects invisible light to surrounding objects allowing it to determine distance based on the reflection time. Coming from a vac that fumbles around bumping into everything, the S31 is a massive upgrade as it maneuvers gracefully around objects and furniture with subtle speed changes, and it can keep a straight path consistently, which isn't always a given.
LiDAR also enables precise mapping that is created during the initial run and improves over time. I am blown away by the mapping's accuracy as it covers every accessible area of my home and how it lends itself perfectly for the advanced features like boundaries and no-go zones. With my previous vacuum, I would have to shut the doors to bathrooms and other areas that I didn't want the vacuum to go in, which was a chore. After a few taps in the app, I was able to get rid of this problem altogether by creating boundaries, putting my mind at ease when it was time for cleaning.
The battery life of the S31 is fantastic, with the vacuum returning to its charging base after hitting every room in my 1,500 square foot home with plenty of juice to spare. On average, the vacuum has between 50-60% charge left when using its normal power mode, and on its highest setting, the S31 would finish with around 30% leftover. A typical run in my home takes the vacuum between 65-80 minutes, so I would say that Kyvol's four-hour estimate is a little generous, but it is pretty close, and it should be good enough to cover most homes.
Now, before we dive too deep into the S31's mopping capabilities, let me first say that it is not a replacement for your old-fashioned mop, so don't expect miracles. I do like how the S31 provides the ability to mop, and it is simple to set up with the snap-in water tank and included removable pads.
When the vac is ready to go for mopping, you switch the vac to mop mode via the app and then tap on start cleaning. During mopping, the app looks and feels the same as vacuuming, with no additional settings to keep everything familiar and straightforward.
As previously mentioned, the S31's mopping is relatively simple as it only offers surface cleaning. The S31 doesn't have any unique vibrations or patterns during mopping that you get with dedicated mopping robots. Instead, the vacuum drags the pads along the floor, using gravity to release water from the tank onto the connected pad.
I found that the mop pads and the floor didn't get as wet as I would have liked during my first run, but I did see better results in later runs by wetting them down before installing them on the vacuum. Again, the vac's mopping isn't going to prevent you from cleaning up giant messes, but it is nice to have as it can extend the number of days you can go between deeper cleans.
The S31's true star of the show is the self-emptying feature, and I am happy to say that it works beautifully. By default, the vacuum will empty itself after every run preventing the dust cup from overfilling or getting clogged, which I prefer. I have been testing the vac for a couple of months now and found that the self-empty system is quite good at removing most of the debris in the bin compartment in the vacuum, as I have seen very few remnants leftover, even after multiple runs. I can also say that Kyvol's 60-day estimate for bag replacements is conservative, at least for my home, as I have yet to fill up an entire bag.
Speaking of the removable bags, while it may not be for everyone, I love how Kyvol's self-empty system utilizes disposable bags versus just having everything going into a bin. My previous experiences with my Shark self-empty vacuum usually end with dust and debris spilling out when it came time to empty it, but that is not the case with the S31, thanks to a handy little cardboard "door" that seals the debris inside of the bag before removing.
Kyvol currently sells a four-pack of the bags in a maintenance accessory set that includes brushes, filters, and disposable mop pads all-in-one convenient kit for $49.99 on Amazon. While that may sound a little pricey at first, the bags again are supposed to last up to 60 days each, and by packaging everything into one kit, it serves as a friendly little reminder to replace some of the critical components, which I like. If you can't quite get over the price, you can always reuse the bag after emptying, and there are, of course, third-party options available.
Smart app and controls
Moving over to the Kyvol app, I like how easy it is to track down options and get the vacuum started. The app's interface is clean, with easy to understand labels for most functions, and it puts essential data and controls all on the same screen. Starting a whole home cleaning cycle requires just two taps, and choosing rooms for selective cleaning is just as easy.
Creating a vacuum schedule takes place via the settings menu accessible from the main overview screen. Scheduling options include specific times and days of the week, plus suction power settings so you can run it at higher levels while you are out and about. I especially like how room-specific schedules are also available, and regardless of which option you choose, the vacuum will respect any boundaries set.
Establishing the no-go virtual borders and no-vac/mop zones is also incredibly easy to set up in the app. After adding a zone or boundary, you can move it around with a tap and a hold, and you can adjust the size by dragging a corner of the default shape. The app supports a total of 10 zones and boundaries, which is plenty for my smaller home, and you can always create additional maps if your home has multiple floors.
Additional options found within the app include the ability to adjust how often the vacuum self-empties, toggling on and off the auto boost mode, and setting volume levels of the on-device voice prompt. The settings menu also houses additional cleaning modes: edge cleaning-only and a full deep clean mode; both activated via a toggle that defaults to off to keep things simple.
I also enjoy seeing how the app displays the vacuum's progress and location on the map in real-time. I love being able to peek-in on the S31 while cleaning as it gives me a better sense of what room it is going to head to next, and I will admit that there have been times where I left the app open to watch as it is just plain cool to see in action.
Along the same lines, I also love how the app keeps a complete cleaning record of the vacuum's activity. The history provides a cleaning map so you can see the exact route that it took, the total duration, date, and area measured in square meters. The app even presents you a handy way to see when it is time to replace "consumable" parts used like the brushes and filter, which is thoughtful.
Kyvol's app unlocks powerful mapping features, voice controls, and advanced options for the Cybovac S31 Robot Vacuum and more.
A little vague
Kyvol Cybovac S31 Robot Vacuum review: What I don't like
As much as I like the Kyvol app features, I ran across several issues that hurt the overall experience. Getting the vacuum paired to the app presented a few challenges, with my first attempt resulting in a "Connection Failed" error after unboxing. I am not quite sure what went wrong in that instance, but my second attempt went through without a hitch — at least until I got to sending the vac out for cleaning.
Before the first clean, the Kyvol app presented me with a prompt for a firmware update, as you often see with most smart devices. Unfortunately, the firmware update process is mandatory before cleaning, and it would fail after just a few seconds. The app's only troubleshooting steps were to ensure that the vac was charging and that the battery level was above 20%, both of which were true. After a failed attempt at finding help through the Kyvol website, I was able to track down a fix from other reviewers that came across the problem. Starting a clean manually via the included remote control first somehow made everything better, and I could apply the firmware update afterward.
Another issue that came across with the app is that it would occasionally show that the vacuum was "Offline" while cleaning. The vac would continue with its route just fine, and it didn't lose its map during these bouts, but it did prevent me from seeing its location in the home and where it had already cleaned. The app would mention possible factors like distance, and despite showing as "offline," the vac never lost its connection with my Wi-Fi router, so I believe that this is a software issue versus a hardware issue.
Finally, while rare, when the robot vacuum did have an issue during operation, the app was rather vague as to what the problem was. For example, once when the robot vac got stuck between my desk chair and one of my desk's legs, the app presented me with a notification that was titled "Start it at another location" and stated "S31Start it at another location", which wasn't helpful at all. Another example appeared when I lifted the vac to check brush conditions, which displayed "It shall be started on the ground" and "S31It shall be started on the ground". Thankfully, most issues will be apparent, but the notification phrasing needs a little work.
The robot vacuum market is quite crowded these days, with tons of excellent options from iRobot, Roborock, Neato, Ecovacs, and eufy. However, when it comes to robot vacs with a self-emptying, the market is much more limited, with only a handful of options from just a few vendors available.
Our current picks for best robot vacuums include the Roborock S5 Max and the Neato Botvac Connect D7. The Roborock S5 Max offers the same LiDAR navigation system and mopping features as the S31, but it costs $50 more lacks the self-empty feature. The Roborock does include the ability to adjust mop water levels, and it works with Siri Shortcuts, making it more convenient for those in the Apple ecosystem.
Just like the S5 Max, the Neato Botvac Connect D7 also includes laser-guided navigation and Siri Shortcuts support. The D7 is more expensive than Kyvol's vac with a retail price of $599, and it doesn't include mopping or the self-empty system, but its unique square design allows it to get into corners better.
The closest self-empty competitors to the S31 — at least with regards to price are the iRobot i3+ and the Shark IQ RV101AE. The iRobot i3+ starts at $100 more than the S31, but it uses a floor mapping system that doesn't include the ability to set no-go zones, and it doesn't mop. Shark's vacuum has a massive bagless self-empty chamber, but it lacks mopping and laser navigation.
Kyvol Cybovac S31 Robot Vacuum review: Should you buy
You should buy this if ...
You want a robot vacuum that vacuums and mops
The Kyvol Cybovac S31 combines both mopping and vacuum into one, removing the need for an additional robot. While the mopping isn't a proper deep clean, it is passable for light, everyday jobs.
You want virtual boundaries and room cleaning
LiDAR technology inside the S31 truly makes virtual boundaries like no-mopping zones and no-go zones a reality, plus it enables individual room cleaning. No unsightly boundary strips to manage or issues with the vacuum going where it shouldn't with the S31 — it just works.
You do not want to hassle with emptying the bin after each run
The self-empty feature on the S31 is genuinely a game-changer if you have grown tired of manually emptying the tiny bin on older robot vacuums. With Kyvol's vacuum, you only need to replace the bin bag once every other month with regular cleaning, and changing it out is incredibly easy and mess-free.
You should not buy this if ...
You want a robot vacuum for $200 or less
With the self-emptying base, LiDAR, and mopping capabilities, the Kyvol Cybovac S31 packs in many premium features, making it more expensive than standard robot vacuums. If you don't care about all of the extras, the S31 is not the one for you.
You expect deep cleaning with the mopping capabilities
While having the ability to mop is handy and a nice to have feature, the S31 doesn't deep clean as it lacks vibration and scrubbing action. If you want a more thorough clean, you will need to look at dedicated mopping robot options.
You are looking for a robot vacuum with Siri voice controls
The Kyvol Cybovac S31 doesn't support any form of voice controls through Siri as it lacks both HomeKit and Shortcuts integration. Kyvol's vacuum only works with Alexa and the Google Assistant for voice controls currently.
If you are looking for a robot vac that provides a genuinely hassle-free cleaning experience, then the S31's self-emptying, mopping, and LiDAR navigation fits the bill. However, if you only want the basics, want to control your vac via Siri, or if you want a robot mop that will keep you from having to mop your floors ever again manually, then you will need to look elsewhere.
App quirks, limited mopping, and lack of Siri support aside, the Kyvol Cybovac S31 is an incredible value that offers excellent cleaning performance, long battery life, and an absolute ton of features. The convenient self-emptying feature is worth the admission price alone if you have ever experienced the hassle that comes with owning a vac with a smaller bin, and the LiDAR navigation is a great place to start for those new to the world of robotic cleaning. Mix in the smart app controls, scheduling options, mopping, and advanced mapping, and you get a robot vacuum that does just about everything — for less.
Christopher spends most of his time writing and dreaming about all things HomeKit and the Home app. Whether it is installing smart light switches, testing the latest door locks, or automating his households daily routines, Christopher has done it all.
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