Testing the Roborock S4 Max Robot Vacuum

We got hands on with the Roborock S4 Max.
We got hands on with the Roborock S4 Max.

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If there’s one thing that’s become clear during the coronavirus pandemic, it’s how dirty a home can get when you and your family are spending basically 24/7 inside. In our house, dishes, dust bunnies, and fur from our two cats (don’t even get me started on the fur, which even pre-pandemic couldn’t be tamed without frequent vacuuming!) just kept piling up, adding to our general stress. So when Roborock offered to send their S4 Max robot vacuum to test, I jumped at the opportunity. I’d never had a robot vacuum before—it can be hard to justify the expense without knowing if one will truly work for you—so I was eager to try it out.

Setting up the Roborock S4 Max

While you can use the Roborock S4 Max by simply hitting the "clean" button, you’ll get the most out of it if you use Roborock’s app, so my first step was to link the robot to my Wi-Fi using that app. I’m not the most technologically savvy person, but the instructions were clear and made syncing everything painless.

Once that was done, I hit the "clean" button in the app, and the robot mapped our apartment as it cleaned using LiDAR. First, it would make a perimeter of the room, then clean the interior following a grid pattern. The whole process of cleaning and mapping the apartment took about an hour—and this in spite of the fact that one of my cats was actively trying to murder the robot.

Mid-map (left) and full map, with rooms identified (right)Erin McCarthy/Roborock App

I’m horrified to report that during that first clean, I had to empty out the dust bin twice (I wasn’t kidding about dust bunnies piling up!). Thankfully, the 460-milliliter dust bin was easy to remove and empty, and the HEPA-Type E11 filter is washable.

After the first cleaning was complete, I separated my apartment map into rooms, which would later enable me to send the robot to specific areas to clean. I also set up some “no-go zones” around areas I didn’t want disturbed, like the space under the bookcase where our Wi-Fi cable is. Users have the ability to set up 10 no-go zones and 10 invisible walls to keep the S4 Max from going where they don’t want it to go—a very handy tool.

How does the Roborock S4 Max do on rugs?

It’s probably no surprise that the Roborock S4 Max easily cleans dirt, fur, and dust from hardwood floors. It also did great with a mess of tiny Styrofoam fragments. But how would it handle rugs?

The Roborock S4 Max cleans pieces of Styrofoam.Erin McCarthy

Right away, I was impressed. The robot comes with four suction modes—quiet, balanced, turbo, and max—and it automatically kicked up to max when on rugs to get up as much stuff as possible. Thanks to its floating main brush, the robot was able to easily maneuver onto rugs with both higher pile and varying pile heights and get them clean.

The real nail-biting moment came when the vacuum got to my dark navy rug. I had a friend whose robot vacuum emailed him something to the effect of “I’m falling off a cliff!” every time it hit their dark-colored rug—but this thankfully wasn't an issue for the S4 Max.

The only rug the S4 Max did have a problem with was the shag rug in our bedroom. It cleaned the rug but struggled mightily, never really achieving the grid pattern it had in other areas of the apartment (see below).

The Roborock S4 Max had trouble with the shag rug.Erin McCarthy/Roborock

And while the robot cleaned the bulk of our bedroom, it never made it over the rug and past our bed to the other side of the room, even though it “saw,” or mapped, the path there. When I replaced the shag rug with a lower pile rug, the vacuum still didn’t make it over to the other side of the room.

Robomax S4 Max Troubleshooting

Thus began a bit of an odyssey to get the vacuum to go to that area. I couldn't find the information I was looking for on Roborock's website, so I turned to Google, which led to YouTube videos that recommended setting up invisible walls or zones to get the vacuum to go where you want it to go.

So I set up a zone in the map and asked the robot to clean it. This solved my problem with the first part of the path, but the robot still didn’t want to clean the second area, even after I’d used the zone trick. When I cleaned the full room, I still couldn’t get it to go completely into the area in gray, below.

Using the zone feature to attempt to get the Roborock S4 Max to go to an area it hadn't previously cleaned (left and middle). Initially, even after using the zone feature, the robot wouldn't clean the area in gray in a full room clean (right). But trying the trick one more time finally worked.Erin McCarthy/Roborock

When I next did a full clean of my apartment, the vacuum didn't go into the first part of the path, either. I decided to try to zone trick one more time, and finally, it worked—the next time I cleaned the entire room, the robot tackled that area, too. I haven't had an issue since.

Scheduling the Roborock S4 Max

One of the best features of the S4 Max app is the ability to schedule the robot to do cleanings—both of the whole map and of specific areas. I chose to set mine to clean the kitchen and the area where I eat on Monday, Wednesday, and Friday mornings, while the office—where the cats' litter box is located—gets a clean every night at 7. You can also set the amount of suction you want for particular rooms, and set the vacuum to go over the area more than once, to ensure everything gets picked up.

The app has other cool features, including remote control and pin and go. In the maintenance section, you can see how much “life” is left in the filter, the side brush, the main brush, and the sensors, both in percentage and in how many hours until they need to be replaced, which is very helpful. (The robot comes with a replacement filter as well as a tool to clean the main brush.) Also accessible on the app are cleaning history, user manual, volume, and vacuum settings, including how long it’s in "do not disturb" mode. You can also hit “find my robot” and the device will announce, loudly, “Hello, I’m over here!” delightfully terrifying anyone nearby. (Apologies to my husband.)

Conclusions About the Roborock S4 Max

While I had a few small issues, overall, there’s a lot to like about the Roborock S4 Max. It gets up a ton of dust and fur, and the scheduled daily cleaning of the office means that the amount of cat litter getting tracked around the apartment has decreased dramatically.

I haven’t quite gotten to the point where I’ve named the robot yet. I often find myself cleaning up for it so it can do its job better (which frankly seems a little silly, but I can't help it!). And my cat is still trying to kill it, so I end up following her as she follows the S4 Max, shooing her away. But overall, after this first robot vacuum experience, I’m officially a convert: Not only does our apartment feel a lot cleaner, I also have a bit more free time on my hands. Now, if only the S4 Max could do dishes …

The Roborock S4 Max has been going in and out of stock recently, but right now, you can order it on Amazon for $430, with shipments going out within the next few weeks. For the rest of Roborock's offerings, head to their Amazon store.

10 Reusable Gifts for Your Eco-Friendliest Friend

Disposable tea bags can't compete with this pla-tea-pus and his friends.
Disposable tea bags can't compete with this pla-tea-pus and his friends.

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By this point, your eco-friendly pal probably has a reusable water bottle that accompanies them everywhere and some sturdy grocery totes that keep their plastic-bag count below par. Here are 10 other sustainable gift ideas that’ll help them in their conservation efforts.

1. Reusable Produce Bags; $13

No more staticky plastic bags.Naturally Sensible/Amazon

The complimentary plastic produce bags in grocery stores aren’t great, but neither is having all your spherical fruits and vegetables roll pell-mell down the checkout conveyor belt. Enter the perfect alternative: mesh bags that are nylon, lightweight, and even machine-washable.

Buy it: Amazon

2. Animal Tea Infusers; $16

Nothing like afternoon tea with your tiny animal friends.DecorChic/Amazon

Saying goodbye to disposable tea bags calls for a quality tea diffuser, and there’s really no reason why it shouldn’t be shaped like an adorable animal. This “ParTEA Pack” includes a hippo, platypus, otter, cat, and owl, which can all hang over the edge of a glass or mug. (In other words, you won’t have to fish them out with your fingers or dirty a spoon when your loose leaf is done steeping.)

Buy it: Amazon

3. Rocketbook Smart Notebook; $25

Typing your notes on a tablet or laptop might save trees, but it doesn’t quite capture the feeling of writing on paper with a regular pen. The Rocketbook, on the other hand, does. After you’re finished filling a page with sketches, musings, or whatever else, you scan it into the Rocketbook app with your smartphone, wipe it clean with the microfiber cloth, and start again. This one also comes with a compatible pen, but any PILOT FriXion pens will do.

Buy it: Amazon

4. Food Huggers; $13

"I'm a hugger!"Food Huggers/Amazon

It’s hard to compete with the convenience of plastic wrap or tin foil when it comes to covering the exposed end of a piece of produce or an open tin can—and keeping those leftovers in food storage containers can take up valuable space in the fridge. This set of five silicone Food Huggers stretch to fit over a wide range of circular goods, from a lidless jar to half a lemon.

Buy it: Amazon

5. Swiffer Mop Pads; $15

For floors that'll shine like the top of the Chrysler Building.Turbo Microfiber/Amazon

Swiffers may be much less unwieldy than regular mops, but the disposable pads present a problem to anyone who likes to keep their trash output to a minimum. These machine-washable pads fasten to the bottom of any Swiffer WetJet, and the thick microfiber will trap dirt and dust instead of pushing it into corners. Each pad lasts for at least 100 uses, so you’d be saving your eco-friendly friend quite a bit of money, too.

Buy it: Amazon

6. SodaStream for Sparkling Water; $69

A fondness for fizzy over flat water doesn’t have to mean buying it bottled. Not only does the SodaStream let you make seltzer at home, but it’s also small enough that it won’t take up too much precious counter space. SodaStream also sells flavor drops to give your home-brewed beverage even more flair—this pack from Amazon ($25) includes mango, orange, raspberry, lemon, and lime.

Buy it: Amazon

7. Washable Lint Roller; $13

Roller dirty.iLifeTech/Amazon

There’s a good chance that anyone with a pet (or just an intense dislike for lint) has lint-rolled their way through countless sticky sheets. iLifeTech’s reusable roller boasts “the power of glue,” which doesn’t wear off even after you’ve washed it. Each one also comes with a 3-inch travel-sized version, so you can stay fuzz-free on the go.

Buy it: Amazon

8. Countertop Compost Bin; $23

Like a tiny Tin Man for your table.Epica/Amazon

Even if you keep a compost pile in your own backyard, it doesn’t make sense to dash outside every time you need to dump a food scrap. A countertop compost bin can come in handy, especially if it kills odors and blends in with your decor. This 1.3-gallon pail does both. It’s made of stainless steel—which matches just about everything—and contains an activated-charcoal filter that prevents rancid peels and juices from stinking up your kitchen.

Buy it: Amazon

9. Fabric-Softening Dryer Balls; $17

Also great for learning how to juggle without breaking anything.Smart Sheep

Nobody likes starchy, scratchy clothes, but some people might like blowing through bottles of fabric softener and boxes of dryer sheets even less. Smart Sheep is here to offer a solution: wool dryer balls. Not only do they last for more than 1000 loads, they also dry your laundry faster. And since they don’t contain any chemicals, fragrances, or synthetic materials, they’re a doubly great option for people with allergies and/or sensitive skin.

Buy it: Amazon

10. Rechargeable Batteries; $40

Say goodbye to loose batteries in your junk drawer.eneloop/Amazon

While plenty of devices are rechargeable themselves, others still require batteries to buzz, whir, and change the TV channel—so it’s good to have some rechargeable batteries on hand. In addition to AA batteries, AAA batteries, and a charger, this case from Panasonic comes with tiny canisters that function as C and D batteries when you slip the smaller batteries into them.

Buy it: Amazon

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Ninja’s Hot & Cold Brewed System Is the Only Coffee Maker You’ll Ever Need


Update: The glass-carafe version of the Ninja Hot & Cold Brewed System is currently on sale for $89 (a 50 percent discount) at Walmart. The thermal-carafe version is on sale on Amazon for $200, a $30 percent discount.

For people who just want a cup of joe to help them get out the door in the morning, the French presses, Chemexes, Aeropresses, Moka pots, and other specialized devices that coffee aficionados swear by probably seem more overwhelming than appealing. Ditto the fancy cappuccino machines at local cafes. That’s where Ninja’s new Hot & Cold Brewed System comes in: It was created to give coffee addicts a myriad of options with minimal fuss, not to mention minimal equipment. And it makes tea, too!

“Coffeehouses are known for having an endless selection, but current at-home brewers haven't given users the vast variety of choice we thought possible, and certainly not all in one product," Mark Rosenzweig, CEO of SharkNinja, said in a press release. "The Ninja Hot & Cold Brewed System changes the category entirely. This innovative system is more than just a machine you use in the morning; it's your all-day brewing partner.”

The Hot & Cold Brewed System comes with two baskets: one for coffee and one for tea. It knows what you're making to make based on the basket you insert, and the available options for that basket will light up. The machine allows the user to make six different sizes of coffee or tea, from a single cup all the way up to a full 50-ounce (10-cup) carafe.

And of course, as the name suggests, the system can make both hot and iced beverages. For coffee, it has five brew options: classic, rich, over ice, cold brew, and specialty (a concentrated brew for milky drinks like cappuccinos). If you’re making tea, you can choose between hot and cold brews optimized for herbal, black, oolong, white, or green tea.

When you select an over ice or cold brew, the machine automatically doubles the strength of your beverage so it doesn't get overly diluted by the ice cubes in the carafe. Even better, the Ninja can make cold brew in just 10 to 15 minutes, whereas other systems and methods typically take hours. (Hot coffee is brewed at 205°F, while the cold brew is made at 101°F.) And the system has a hot and cold frother that folds into the side so you can make barista-level lattes, too.

These bells and whistles sound impressive on paper, but how do they perform in real life? Ninja sent me Hot & Cold Brewed System to test for myself.

Ease of Use

Though it might look like something developed by NASA, the Hot & Cold Brewed System is designed to easily work with the twist of a dial and the push of a button, and it delivers. From loading in the correct amount of grounds with the system’s “smart scoop” to picking what type of brew you’d like, it’s simple enough to use even while bleary-eyed in the morning. It’s also easy to schedule a delayed brew so you can do the rest of your morning routine while your coffee brews. (Here’s the only drawback I can think of about this machine: When it starts brewing, it’s kind of noisy—loud enough to make my cats jump. It’s not a dealbreaker, but if you live in a small apartment and plan to brew coffee so that it’s ready right when you wake up, it might be something to consider.)

The system even tells you when it needs to be descaled. The “clean” button will light up, at which point you simply fill the water reservoir with descaling solution and water and press the clean button. A countdown lets you know how much longer the clean cycle will last.

Taste and Flavor

I swapped out an old, cheap coffee maker for the Hot & Cold Brewed System, and the difference was immediately noticeable. Whether hot or cold, the coffee made by the H&CBS was a better, smoother cup of joe. That’s due to what Ninja has dubbed Thermal Flavor Extraction automated brewing technology, which, according to a press release, “knows the precise temperatures, correct bloom times, and proper levels of saturation for every possible beverage combination to ensure a great taste every time.”

Whatever tech they use, it works. The coffee I make in this machine is consistently tasty. The rich brew setting works exactly as advertised, too, providing a richer, bolder flavor than the classic brew.

Features and Accessories

One of the best things about the H&CBS is the fact that it cuts down on waste significantly. Unlike other machines, it doesn't require any plastic pods or paper filters. Instead, it comes with two permanent filters, one for coffee and one for tea.

And the cold brew function is a game changer if you prefer iced coffee to hot. Not only does it brew quickly, but it eliminates the messy cleanup that comes with making cold brew yourself.

Typically priced at $230 for the thermal carafe version (or $200 for the glass carafe, though both are regularly on sale), the Hot & Cold Brewed System is significantly more expensive than a simpler drip coffee machine. But if you’re a cold brew addict looking to treat yourself, it’s worth it. Consider springing for the slightly more expensive thermal carafe model, which will keep your java hot or cold for hours. (I’ve left ice in it overnight and found cubes the next morning.)

You can get the Hot & Cold Brewed System on Amazon, Walmart, or Macy's starting at $89 right now, but those prices are likely to rise back up soon.