Review on Airmon Palm PM2 5 Quality Monitor by Teri Washington

I live on the west coast where wildfires affect air quality. I recently bought an air purifier but it doesn't have an air quality sensor built in so I bought it to try and measure how well it works. I wasn't sure how well it would work when I bought it, but due to Revain's return policy and how cheap it is compared to other options, I had to try it. Other options I saw cost over $100 and didn't have smart connectivity. For only $200+ there is something with WiFi included. Mind you, it doesn't, it uses Bluetooth, but it's a lot more convenient than a low-tech portable handheld device. Unless you're trying to do remote sensing or some sort of home automation that turns the air purifier on or off, etc., you don't need WiFi. Firstly, yes the instructions are mostly in Japanese and yes you may run into problems. I'm trying to get this thing to work. When I got it, I couldn't get it to work despite restarting the device, restarting the app, or turning Bluetooth on and off on my Android phone. What really helped was manually pairing the device from the Bluetooth settings. It paired with the app showing it's connected in the Bluetooth settings and the LED chain flashed in sequence to indicate the device was communicating, but it ended up with a timeout message. I don't know what manual device pairing is, but that's why it worked. How do you know it works? The app will show you a 15 second countdown timer and tell you what it's measuring and you'll hear the tiny vacuum cleaner sound coming out of the cube (see video). It then gives you the results in pm2.5, pm10, temperature and humidity. I did a few test runs to get an idea of the accuracy. First I ran it outdoors several times and compared it to local air quality readings online (IQAir AirVisual). What I found was that the temperature was always accurate to within a degree, the humidity was measured 5-10% higher and the 2.5 o'clock values varied more (I couldn't find any 10 o'clock values close by ). It's hard to put a percentage of accuracy on it. At worst I have seen other local readings of 40 for pm2.5 while this one was showing 20 while at other times it was within 5% of the value. Indoors, the output of a HEPA purifier is usually read from 1-4 for pm2.5 and 1 or 2 for pm10. It never read less than 1 for either of them, so I think it's effectively a null read. It showed 6 once, but when it ran again it showed 4 or less. So you'll probably have to try it three times in a row and average it for yourself to get a better understanding. Communication is pretty good after initial issues are resolved. I saw him working 30 feet through some walls. It has had to be reset a few times since I got it, 150 readings later. It took 80 readings from a full charge before the battery died. I also tried installing and connecting a tablet and both were able to take measurements independently. The app is ok, could definitely be better. There is an option to export CSV to email, but I noticed that PayPal launches on my device and I couldn't figure out how to fix this mapping. You can view the history of past measurements in the application, although for some reason the time got mixed up (wrong time zone and even the minutes do not match). Note that you can change C to F by clicking on the timeline, but there was no place to set the time zone. Overall, I give it 5 stars because of the value for money. Otherwise I would give it 4 stars for acceptable performance and an app with limited features. EDIT January 2021: Deducted a star because the device will drain its battery and die even if it is turned off before the week is up. In other words, if you've never used it and it was off, it won't turn on when you try after a week. I was hoping that a firmware update would fix this issue, but there have been no updates at all since I received the device. Since the device can work while charging, it can be used as otherwise it would be a much bigger problem.