Honeywell Home T9, the first Resideo thermostat for consumers to support remote temperature sensors, has finally brought a feature that has long been promised to its users: HomeKit.

The brand, which is licensed by Resideo and detached from Honeywell in 2018, already has support for Apple's smart home system in its T5 thermostat, also known as the Lyric T5, but that device has no external sensors. The sensors can help make sure you feel comfortable in the room you are in, rather than maintaining the desired temperature where the thermostat is.

As Virgin editor Dan Seifert wrote in his review of the Honeywell T9, its sensors are very good and able to measure humidity in addition to temperature, which neither remote sensors from Nest nor Ecobee can do. They can also detect movement and presence and adjust the system to the rooms where people detect. The T9 costs $ 199 and comes with a remote sensor in the box, with support for up to 20.

According to Resideo, with HomeKit integration, users can control their Honeywell Home T9 smart thermostat using Siri or the Apple Home app. Once connected, you can use automation to adjust the temperature or you can ask Siri to do it for you. Unlike the Ecobee SmartThermostat, there is no built-in voice assistant, so you need to use a HomePod Mini, iPhone, iPad or Apple Watch to invoke the assistant. Resideo did not specify whether you will be able to use the temperature or motion of the sensors to trigger routines in the Home application. Honeywell Home T9 already has support for Amazon Alexa and Google Home.

Whether this really matters, given that smart thermostats are in the first Matter specification (the new smart home standard that promises to unify connected devices in our home), remains to be seen. Resideo is on the board of the Connectivity Standards Alliance, which oversees Matter, so it looks like its thermostats will become Matter activated when the standard is released next year. This should mean that users can control their thermostat with any smart home ecosystem of their choice, as long as they accept Matter.

But in the meantime, T9 owners will be able to keep their toes up this holiday season with just a few words to their Apple voice assistant.