ThailandAirGradient builds open-source indoor and outdoor air quality monitors that track PM2.5, CO2, temperature, humidity and other pollutants. The company is known for its open hardware and firmware, letting users build, repair and integrate the monitors with platforms like Home Assistant and its own dashboard. AirGradient appeals to people who want transparent, data-driven air quality monitoring rather than a closed black box.
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Apollo Automation is a smart home maker focused on local, privacy-first sensors built around ESPHome and Home Assistant. Its lineup includes mmWave presence and motion multisensors, air quality monitors tracking CO2, VOCs, temperature and humidity, plant and leak sensors, plus hubs and accessories. Apollo emphasizes open-source software and 3D-printable, customizable hardware with onboard buzzers and RGB LEDs, and runs with no cloud and no subscription. Devices are Made for ESPHome and Works Locally with Home Assistant certified, appealing to users who want affordable, fully local automation.
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