As many of you know, I am a wheelchair user with limited hand function, so I follow residential Handsfree device releases pretty closely.
I’ve been reading the beta reports on Hiome for a while, and it looks promising. Very expensive compared to Zooz or Aqara motion Sensors, but it’s really for a different purpose.
I have a friend, also a wheelchair user, who has one on pre-order and he’s going to try it out next month, so I’ll add an update to this thread after I hear more, but this is starting to get press, so I thought we could use a thread specifically in a smartthings context.
WHAT IT DOES
It’s a local thermal tracker (no cloud!) that counts people as they go through a doorway. And it knows what direction they were coming from. So it knows how many people are in a room and it knows when that changes. It does not know which people are which.
You don’t have to carry anything with you: it’s just a thermal scanner. Based on the beta reports, it ignores cats but probably will count dogs over 40 pounds.
They initially had a problem with wide doorways, but seem to have fixed that.
You need one sensor per doorway that you want to track.
In some configurations it can also work as an open/close sensor, but I’m not quite clear on the details of that.
You need to have its hub, called Hiome Core, because that’s what keeps track of everything.
When you watch this video, don’t pay attention to when the light comes on: you can do that with a motion sensor. (At least the first time someone comes in a room.) Pay attention to when the light goes off. And note that there is no “cooldown“ period When motion might be missed. And finally, note the people counting where it’s not turning off until the last person has left the room. 
DOES IT WORK?
Similar technologies have been used in commercial environments for a while, but up until now the ones released for residential use were not very effective. This one seems to be good but it uses a lot of power. Although they do offer a rechargeable battery version, the add on itself is huge, like salad plate size huge, and the battery will only last about a month between charges. So you really want to use mains power.
They have both a plug-in version and a recessed version, but both are going to be noticeable for people who notice things like that.
Here’s the battery version. I could live with this if it had a one year recharge cycle, but reportedly it’s 3 to 4 weeks. 
Integration
Most people seem to be using it with Homekit, where it gives you two actionable tiles, one for occupancy and one for open/close.
Here’s one independent blog review from a beta tester:
But there are also some people using it with MQTT, which I think would be the preferred smartthings integration.
Some people will also be able to use it through their hue Bridge, but only indirectly. You can have the Hiome Sensor trigger a hue light to come on and then have that Hue light coming on trigger others smartthings events. This is a much more limited integration than HomeKit or MQTT, but it might work for some people.
Back when they were in pre-launch phase the company said it was going to have smartthings integration and IFTTT, but neither of those occurred. I was told unofficially by a beta tester that they decided to go for all local solutions instead because they really want to hit a 200 ms response time consistently. I don’t know if that’s true, but it is consistent : these folks are really big on privacy and response time.
The COMPANY
Little tiny Chicago company. Once you have everything set up, the devices should still work even if the company goes out of business since everything is local.
I congratulate them for their commitment to engineering and for a dropping Google analytics as untrustworthy. But I don’t know anything about them other than what’s publicly available.
The Cost
High. Not as bad as similar commercial systems, but it works out to about $100 per Sensor. And if you only buy one sensor and the hub, that’s about $200.
Also, as a tiny company they have made the decision to fulfill all the starter kit orders first, so although they eventually intend to offer add-on sensors, for right now, you can’t buy the sensors individually. So if you want 10 sensors, that’s what you need to buy in your first order.
As most people know, I don’t normally comment on pre-release devices, particularly the ones which are just marketing materials, but these have been in beta for about a year and there are several independent reports on them and I know this is a technology many people are interested in, so I decided to go ahead and post this. Again I’ll update more after I’ve had a chance to actually see some.
BTW, @jelockwood first mentioned this device in the forum about a year ago when it hadn’t even gone into Beta yet. It’s nice to see that they do seem to have made it out of the prototype stage. No telling whether the company will survive, but the technology is interesting.