18-in-1 Smart Air Quality Monitor – Indoor WiFi Air Quality Detector with Dual Chip, Real-Time for AQI, CO2, PM2.5, PM1.0, PM10, TVOC, HCHO, Time, Temperature & Humidity with APP (White-Black)

Well design. Easy to set up and operate. Monitor most important pollutant
This is my second air quality monitor. I bought the previous one 6 months ago and it does not monitor as many pollutants as this monitor. This machine monitors PM 2.5 which my other monitor does not cover. This air quality monitor is easy to set up and operate. It runs itself after you set it up. The large led display is easy to see especially with the color code. I can glance at it and know the air quality right away. When the pollutant exceeds a threshold, It will sound an alarm to alert me. I tested it with cigarette smoke and it worked well. Real time monitoring and operate via the App

These absolutely do not work. Horribly unreliable/inconsistent readings.
I so wanted these to work. And yet here I am, giving the first one star review I’ve ever given– and feeling bad I could not select zero starts. I was hopeful when it arrived and was pretty easy to set up. I started watching the numbers… and placed it on the counter so I could see what was going on. It very quickly started sounding alarms for CO2, but I remembered it takes 24 hours to calibrate itself. The next morning it still showed CO2 beyond the red levels. So I put it outside in the fresh air. CO2 normalized somewhat, down to low 400’s. Brought it back inside, and alarms sounded. It was literally still in my hand, only steps inside the door. Mind you this is a house with living people and pets– so probably not really at 1500+ CO2. After multiple attempts I figured I got a bad unit and set up a return. I still wanted it to work, so I had a replacement sent. It arrived and I had the idea to run them side by side. I kept records of Unit 1 and Unit 2 over a few days. Unit 1 continued to alert me with crazy high CO2, HCHO and TVOC. I powered the units off, restarted, took them outside– I tried to give them a chance to prove themselves. Unit 1 always had higher CO2 than Unit 2– usually by about 400 points. Neither unit ever went below 400 for CO2 even when outside. On the 3rd day, Unit 2 wigged out and was 300 points higher on CO2, 8x higher on HCHO, and about 15% higher on TVOC– while they were on the counter about an inch apart. Probably should note they were also always 1-2 pts different on temperature and humidity. Similarly the two units were always about 2 pts different on AQI, and 102 pts different on PM2.5. I wondered if CO2 was just not working at all– so as a test I exhaled 3x on each one. Both responded by increasing the readings, then gradually normalizing. So some part of it’s working. The units just register numbers 300-400+ different under almost all circumstances. Unit 1 continued to sporadically show alarms level readings for TVO when Unit 2 would show 0. By the fifth day, having recorded measurements many many times a day I realized there was no way to trust the functionality of either unit. It does not measure air quality, or any of the components satisfactorily. There is NO value in this product. This product has not been adequately tested and it’s a disservice to be sending them out to people who need or want to know about their air!

Sensitive and accurate
I’m so glad I went with this air quality monitor. It’s very sensitive and picks up someone lighting a cigarette within seconds. I have a three level home and I tested it in all three as well as outside and it gave me different reading quickly. I ordered better quality air filters the same time as I did the monitor but the monitor arrived the day before. Around two hrs after I installed the new filters I was able to visually see the difference they made in my home on the graph on the app. The app is free to use and doesn’t need a subscription & has the option to add smart devices. The quality is outstanding for the price considering how sensitive it is and I now know that my homes air was definitely contributing to everyone getting sick so often as well as getting random sore throats. I have 4 small children in my home and three are babies. The air quality in my home was very dangerous for them and I didn’t even know until I purchased this monitor. It works and is very easy to set up. I can’t say enough good things about it. I’m so glad I decided on this one.