Spotted by Dave Zatz, an under-the-radar feature that’s also showed up in iOS 15.1 beta 2 is the option to use a HomeKit humidity sensor to create automations.

A research team develops a real-time humidity sensing optical sensor. The response time of the new sensor is 10,000 times faster than the conventional sensors and can be mass-produced at low cost.

Researchers describe a humidity sensor inspired by the structure and properties of camels' noses. In experiments, they found this device could reliably detect variations in humidity in settings ...

Hidden within all models of the Apple HomePod and HomePod Mini are a temperature sensor and a humidity sensor, this was enabled with the most recent HomePod 16.3 software update.

Activating the temperature and humidity sensors isn't the only thing Apple delivered with this software update. HomePod mini owners get lots of new functionality that we wanted to put to the test.

The temperature/humidity sensor feature should be unlocked with today’s iOS 16.3 release, which also brings support for the upcoming HomePod, along with various security-minded updates.

Renesas's HS400X families of relative-humidity sensors deliver results within three seconds. Very low current consumption: 0.3 µA average for 8-bit resolution with a 3.3-V supply Ultra-low sleep ...

These sensors, especially including the breakout boards, are rather bulky as well, making them hard to integrate into projects. At some point we came across this MEMS sensor from Bosch, the BME280.