Indoor air-quality monitors that track particulates and gases.
AirGradient is a Chiang Mai company making fully open-source air quality monitors. Its One Indoor Monitor (I-9PSL) is sold as a self-assembled kit or fully assembled, offering an affordable, hackable way to track indoor air.
The Aqara TVOC Air Quality Monitor measures temperature, humidity, and total volatile organic compounds. I bought it to watch the air in my newly renovated home, where fresh carpentry gives off chemical compounds.
The Atmotube Pro is a portable air quality tracker, the company's fourth product. Pre-orders opened in February 2019 at US$131, shipping that April, with a US$189 retail price thereafter. It's now on Amazon.sg for S$215.
uHoo is an indoor air toxin sensor launched in April 2017, shipping first to corporate customers, its primary audience, then to general consumers from June. Backed by an East Ventures seed round, it had earlier crowdfunded pre-orders on Indiegogo.