It detects when there are particles in the air and cleans automatically. It makes a little noise if it's on Max.

The air purifier covers a room and within half an hour, at full intensity, it manages to clean the space from odors. At low intensity during the night, it does not manage to cover the space satisfactorily. The price of the filter is satisfactory.

I have had the Mi 2H for many years, and recently the 4 ... both of them, especially the 4, are perfect!
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The day before yesterday I also received the Compact for the guest room.
It does a very good job for the 14sqm.
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Just the filter is half the size of the others and costs almost the same money.
I would suggest you better get a Xiaomi with the bigger filter.

Originally bought to keep allergens low in the house living room, use it daily to keep room refreshed.

I haven't figured out yet if it actually cleans, but when we once used a deodorant with powder, the indicator turned red showing that the air quality was bad, so it does detect dust, microparticles, etc. It has low noise but that also depends on the settings you choose, its installation on wifi and on the phone is easy, and the app has various options for speed, how many square meters you want to cover, etc.

Very good, it really works and detects immediately after a few seconds in the atmosphere if someone lights a cigarette even if they are not nearby... also when you cook (frying) and you place it somewhere in the kitchen, for example at a distance of 2-3 meters from the frying, it immediately turns red and works at full power (on automatic mode).

For electronic cigarettes, however, there is a BIG difference from regular cigarettes... it detects that the air is not clean much more difficultly... two people have to be vaping constantly and producing a lot of vapor and still it doesn't work at full power... whereas with one cigarette it immediately goes full power. You should buy it, it's worth it... it cleans up to 50sqm (with more difficulty of course) but it does it.

Attention!! It is very good for cleaning the atmosphere, e.g. smoke, microbes, etc., but NOT for odors! For odors, you should go for a more expensive and bigger one with a proper activated carbon filter

I shouldn't have even given it 1 star. I bought it because of the 125 reviews here! I live in a 29sqm studio and I smoke electronic iqos. I bought it because in winter I can't have the windows open all the time and the place has a heavy smell from the cigarette, so I wanted to buy it to clean the studio! It did nothing!! Many said it's noisy!! Where, guys???? In sleep and auto mode, where the fan barely spins?! When you set it above 40% through the app, it starts buzzing quite a bit! I kept it for 1 day! In the morning I left for work, I came back late in the afternoon while it was running at 80%, I walked in and the house smelled musty! I have no opinion about allergies and asthma - yes, as you said here, it might help you! Yes, for regular cigarette smokers it might do something... in my case, nothing!
Thank you to Skroutz and the store that accepted my withdrawal and processed a refund.

I use it in a room where I smoke, and yes for a month it absorbed the smoke just fine, the smell doesn't go away completely but it's obvious that it does the job compared to how the room smelled before, even with the window open. But we reached one month, and today I noticed that the air coming out from the top when I turn it on, even without having smoked, smells like cigarette smoke, resulting in the room starting to smell like cigarette smoke even before I light a cigarette. In short, it needs a filter change after one month if used in a smoker's room.

After a month of use, I will say the following. It has significantly reduced the dust in the space. Before, I used to dust on Monday and by Tuesday I had to do it again. Now I dust once a month without exaggeration. On the black furniture I have, the difference is incredible. I think it is clearly visible on the filter as well. As for the smell, it also does an amazing job. Many times I smoke inside the house and when I return from work you really can't tell that someone has smoked inside.

When it works, you feel a change in the room's air but nothing special. The automatic function it has is completely non-existent under normal conditions. If smoke, steam, or something else goes towards the sensor, then it works.

Purchased because it was under 100€, used in the bedroom and more rarely in the living room. It significantly reduces cigarette smell and atmosphere. On the opposite sofa, you can coexist without coughing! Prefer the strong mode!

When I smoke joints, it filters the tobacco but not the weed. Also, the filter loses its lifespan without me necessarily using it a lot. Another thing is that I would like it to have more programming capabilities for its operation, specifically to be able to set it to auto mode depending on the concentration of smoke so that I don't operate it on idle without reason. Nevertheless, 5 stars!!

Very good, for home use, for children, it also works for smoking but if you smoke occasionally if you are smokers obviously this is not what you are looking for, it also weakens the smell from pets.

As an owner of two Jack Russells and a smoker, I can say with absolute certainty that it has changed the quality of life in the house... From the very first day I set it up, I noticed a huge difference.

The atmosphere in my home is now much cleaner, even with my two lively Jack Russells running around everywhere. The HEPA filter manages to completely remove the hair and odors from the dogs, which was always a small problem before. But the best part is that it completely neutralizes the smell of smoke! It's impressive to walk into the room and not smell any smoke at all, even if I smoked 10 minutes ago.

The Mi Home app helps me control the device easily, and seeing the air quality in real-time makes me feel like I'm investing in the health of both myself and my beloved pets. The sleep mode operates so quietly that you don't even notice it.

I bought a second one on sale and I’m looking forward to putting it in the bedroom.

The difference in the air quality of the children's room is huge; all the odors that existed disappeared as if by magic in no time. And because my child has allergic asthma, I believe that with this, he will calm down and the medications will be reduced. My advice is to follow the instructions, especially regarding the side distances; otherwise, the cleaning won't be done properly, no matter what brand you use. The next day, as soon as he turned on the nebulizer for the treatment, the cleaner, due to the medication, started working crazily, so it does what it promises. I should add that for cigarette smoke, it’s better to have it higher off the floor because warm gases like smoke will never go down for it to detect but always rise (Simple physics). And as much as possible, there should be no obstacles nearby.

It is doing perfectly, what it suposed to do. We bought it after baby born. I like, that its indicating automatically if it needed to work on higher speed after smell from kitchen comes to room and air clean after 20 min

It cleans the air from smoke relatively quickly and after a few hours the smell of smoke. There is a smell of smoke in the space that, however, does not remind of smoke but of stuffiness.

- An excellent feature of the device that I haven't seen mentioned before is that you can schedule the device to operate whenever you want for as long as you want during the day. I have it scheduled to run 12 hours a day, one hour on, one hour off, whether it's on auto or manual.
- It cleans dust and airborne particles, and I can see this in the filter, but I also feel it in my nose and the cooking odors after some time.
- As for the air quality indicator, I assume it is based on Chinese standards, so I don't consider the indication particularly reliable.
- The app is very good, and besides setting when it will turn on and off, it gives you the option through a slider to choose many different speeds for the fan.
- Power consumption, from 2 to 23 watts.
- Noise, from silent to "shut the f@#k up"......

It does a relatively mediocre job, but its worst disadvantage is its measurement, which has nothing to do with reality. More specifically, the reading is stuck at 3µg and hardly ever changes, or changes with a significant delay.

Was easy to setup, I keep it on every day and in auto mode during the day works silently, when cooking it starts to work loud and intensive and gets rid of food smell pretty fast, air feels fresher if you can say so.

First day of operation and I am disappointed regarding the sensor. In a 12 square meter room with the door closed, I smoked about half a pack of IQOS and the sensor constantly shows green while the space is obviously polluted. Perhaps the thresholds for it to change to yellow are excessively high, or maybe the sensor lacks accuracy, or perhaps ultimately IQOS is less harmful than I expected. The sleep and auto functions are practically useless for someone who smokes because they operate at such low speeds that I wonder if it recycles the air even once in four hours. The only way to operate at high speed is through the Xiaomi Home app unless the air is extremely polluted in auto mode. Perhaps smokers need to switch to a more powerful device. I’m not saying it’s ineffective. The air is significantly cleaner than before; it’s just that when you smoke, it needs to be constantly on full, and even then it doesn’t cover 100%.

Excellent choice for a room where the door closes to warm up the air conditioning along with the combination of the humidifier from the same company; now we sleep much better. It is also silent.

I run it on automatic and it is very quiet. You have to smoke next to it or have it in a very dusty environment, etc., for it to start making noise.

It does what it promises, and the difference in use for a smoker is obvious. The connection with the App is super easy, and it allows you to check when the filter will run out and when you'll need another one.

The measurements the device makes may be accurate, but until it ramps up for stronger operation, the air quality has to get pretty bad. Practically, this means that if you want to keep it below 5mg/m3, don’t expect the air to deteriorate enough for it to do it automatically. Set it to manual and increase the power. If the idea of manually operating it for optimal performance doesn’t appeal to you, then don’t buy it; there are definitely better devices for you. On the other hand, if you smoke, the air will definitely go to waste, and at this level, the machine will automatically catch that and indeed clean it.

It does a very good job even in larger spaces, effectively pulls in odors and dust.

Connected immediately to WiFi!
All night it was silent in sleep mode!
All night from the very first moment until morning, the room did not smell!
Beautiful! Small! Lightweight!
7/13/24 re-evaluation: smells from the fire in Varnava came into the house and the atmosphere was suffocating... We had locked ourselves in the bedroom with the purifier, air conditioning, and closed shutters, windows, and curtains, and it smelled like nothing!!!

I don't know if it's a problem with this particular device but it is NOT silent, I can still hear it operating in sleep mode