It's been a while in coming, but Meross has finally added a HomeKit-compatible version of their Smart Oil Diffuser to their smart home lineup of products, which now includes a fairly extensive range of devices - smart plugs, lights, strips, garage door openers, and smart switches, etc.

I saw "a while" for two reasons; first, they have had a smart diffuser for at least a year, although at the time it was only compatible with Amazon Alexa and Google Assistant. Second, until this device emerged, there have been no other diffusers with HomeKit support since the introduction of the Vocolinc Flowerbud way back at the end of 2018! Since then, we've seen Vocolinc take on the much larger MistFlow, which serves as a humidifier, although it can also function perfectly as a diffuser, in addition to the much smaller Vocolinc Ripple.

Still, for Meross fans, you now have another option in the "diffuser" HomeKit space, and the Meross option does have an advantage over the Flowerbud, namely the water reservoir, which comes in at 400ml/13.5 floz compared to the Flowerbud's 300ml/10.1flozand the Ripple's rather paltry 200ml/6.76floz. All this despite the fact that the Meross version is actually smaller and lighter than the Flowerbud.

The design of the Meross Diffuser is in some ways similar to many other diffusers on the market, using a faux wood trim, two physical buttons on the front, and a thin LED ring light around the bottom half, which is exposed to HomeKit as a separate 'service', so essentially you get two devices in one - the diffuser and a light, both of which can be used in scenes and automations. It uses 2.4GHz WiFi as expected, so unfortunately no Thread functionality, and unlike the Flowerbud (with which it will no doubt be constantly compared), it does not have a built-in humidity sensor. although many users have said the sensor is inaccurate to the point of being useless.

the Meross smart WiFi Essential Oil Diffuser (MOD100HK) is not yet officially on sale, but can be purchased online through the Meross store for US$59.99, with only a US power adapter available at the time of writing. This listing also notes that because it is not yet officially for sale, and is a "beta version," while it will ship with the required HomeKit code, your Home app may report that it is an "uncertified accessory," which is standard for unreleased beta products.