I've gotta admit, while I've seen the utility of a Homekit-integrated thermostat, and I can imagine situations where lighting could be useful, I'm having trouble seeing the value in an air purifier. I guess if it has a really good sensor you can track the air quality in your house so you know whether it's doing its job or something?
Ahh, wait, I guess tracking whether it's actually cleaning the air is more important than I thought. Who cares if it's got fancy cloud integration skills if it can't actually clean air?
I agree I can't see the value here. I'm more sympathetic than most people to Smart/HomeKit devices, but I'm having a hard time seeing what justifies this.
There's value in having a sensor for "indoor air quality" (though, to be honest, you have no idea quite what you are getting...
The [awful, do NOT waste money on it] Netatmo Home Coach measures CO2 (or at least claims to, it's useless).
The (pretty good) Eve Room measures VOCs (so basically outgassing from plastics and paint).
What you may want is PMIC (density of very small particles; this is essentially what AQI is, and what rises massively with fires). I haven't seen a HomeKit device that reports this, but you can get standalone boxes (look like a small Echo Show) on Amazon that display this and seem accurate (they go up and down as I would expect, numbers look like what I would expect). They're not ideal boxes, cost maybe $50, and don't even include enough networking to give you an auto-synching clock :-(
Anyway, point is, there are multiple ways to SEE your indoor air quality today, much cheaper than what is being offered here, and with other advantages (like it's convenient to sit the Eve Room on your dresser and easily see its constant display of humidity and temperature).
On the other side, suppose you want to purify your air (and you should; as you get older you will realize that lungs are about teh weakest part of the human body! Once you have seen enough relatives or older friends going into hospital you'll see the pattern that it's always when the lungs go bad that things go seriously downhill.)
Easiest way to do it is just run your AC fan frequently with a good filter attached and replaced as often as necessary. In any decent system just the AC fan, no cooling, should take pathetic amounts of power (mine takes 30W!). So you can track that against whatever you are using to measure air quality and see how well it works. In my house I can clearly see the dips in air quality as measured by Eve Room (ie less garbage in the air) whenever the AC switches on.
Use the AC filter (which is ducted to recirculate INTERNAL air). If your house has a whole-house fan, that's something different either to ventilate the house or to cool it, and it pulls in outside air. Good for ventilation/cooling, not good for filtering...
If you feel the AC fan is not enough (but seriously, try it, you might be surprised... And change your damn AC filter -- those things get FILTHY after three months!)
then get a "normal" air purifier, ie the sort of thing recommended by Wire Cutter, or whatever brand Costco is selling cheap this month. A nice big one, (physically big, like a large hand carry suitcase, but they are not heavy) suitable for a big bedroom plus spillover area, should be under $200 and last a long long time. For a small office you should be able to get for under $100.
You don't need to pay for high tech; the things are so simple and use so little power, that there's no value to having WiFi connectivity or scheduling via your iPhone or whatever! Just plug it and let it run 24/7 (again, mine in the bedroom uses 5W and is quieter than ambient traffic noise, so, seriously! why would you bother with schedules and ways to control when it switches on or off?)