M10i

Bit pricy but satisfied with product I checked with different PM 2.5 meter and value matches

I can't tell how accurate it is - but it does react to smoke, fragrances (like essential oils), and so on. I like it. I did not connect it to Wifi and I am not sure I ever will - the app on the App Store looks super sketchy - the title is not even in English. Maybe I should have bought the cheaper (no Wifi) model. But I am not complaining, this thing seems to work.

The sensor looks great and easy to setup. The displayed numerical values are in the same range as the what the my smart air filter is saying, so I guess they are either both correct and both wrong. It would be nice to have one day battery life, mine runs flat after about 4.5 to 5 hours. It is located near a USB wall charger socket, so it is not much of a problem to charge it.

Very fast

I'm using this unit in a home woodshop primarily to keep an eye on particulate matter from sanding and cutting, VOCs from finishing materials, and to monitor how well my dust collection and filters are working. Important to note, this is not an industrial hygiene tool. I find it useful and accurate to assess trends, but am still using ventilation and PPE. I have found it to be pretty responsive in the way that I would expect, spiking shortly after sanding and lingering or dropping depending on distance from the sensor and whether dust collection is running. I also have a second one, and side by side comparisons are very reasonable (some variance is normal in any measurement, but PM2.5 is usually within 1-2 ug/m3 of each other for example). The WiFi capability is very nice for remote measurements, and the app is great about allowing you to download the raw data for recording or analyzing further. Battery life is okay, but you really don't want to have to run it unplugged for more than an hour or so. It can last a few hours but if it's somewhere unplugged that long it usually means I've forgotten about it. One thing to note is that the HCHO and VOC sensors are hyper-sensitive to alcohol vapors, so if you are using rubbing alcohol or open a can of shellac anywhere near it the readings will skyrocket and remain saturated until you do several complete air changes or move the sensor. Overall I find it really useful, with reasonable expectations that should be the case for any analytical measurement tool.

This TEMTOP M10i WIFI AIR QUALITY MONITOR (for PM2.5 TVOC AQI HCHO; Real Time Data Recording) works well, and seems to be accurate enough for my purposes. When I opened a bottle of nail polish in a nearby room, the monitor’s HCHO (formaldehyde) and TVOC (total volatile organic compounds) numbers shot way up. They returned to more normal levels after a few hours. In fact, I liked this device so well, I purchased another, to keep track of the air quality upstairs as well as downstairs in my home. At first, I had difficulty getting the second device recognized by the app and connected to my home network. However, it IS possible to have two wifi devices displayed in the app. Once the devices are set up, they display separate real time readings, and keep independent data histories. (See my photos--one of them has been enhanced a little to make the figures and the device names “Air Quality” and “Air Quality 2” easier to read.) CONNECTION TIPS: The key things to know about the wifi setup are as follows: (1) your phone or tablet (with the app) has to be connected to a 2.4Ghz network; (2) the Temtop monitoring device has to be reset with a paperclip so that you see an “ascending” wireless signal (not just a blinking wireless signal), when you’re joining the home network; and (3) any other Temtop monitoring device already connected to the network should be turned off when you’re connecting the new device. I’m not positive that step 3 is required, but my second device would NOT connect to my network until I turned the first device off. After you get the Temtop devices connected, you can reconnect your phone or tablet to a faster 5Ghz band, and the Temtop app will still work. AIR QUALITY HISTORY TIPS: First, the air quality history comes up in the app when you tap the area that shows the real time readings. Second, if you try to bring up the history and you see “no data”, you may have to (1) turn the device off and on again, and/or (2) log out of the app and log back in again. Clearly, it would be nice if the app were less “uppity”, but the air quality monitors seem to be quite responsive to changes. My upstairs monitor shows consistently higher TVOC readings, for example, because the upstairs has more shampoo, Lysol sprays, etc. in regular use. Once an aerosol spray gets into the air, it will take several hours for it to clear. Also, it would be nice if the app could be set to show local temperatures in Fahrenheit rather than Centigrade. That’s a quibble, though. I haven’t owned my two devices for very long, so they may stop working prematurely (as other reviewers have reported). However, I’m happy with them so far--especially with the real time and historical data available through the app. You can use the app to set your device to record data at certain intervals--starting at as often as every 10 minutes. I do have to keep the devices plugged in all the time, because the battery drains so quickly. The battery doesn’t last anywhere close to the promised 6 hours.