Been using Apple Home app for a few weeks now with the main integration being with the Insteon hub and subsequetly all their devices such as replacing all our homes switches with switches and scene switches, as well as replacing outlets with their smart outlets. Bit of a nightmare to install with Insteon's limited wiring diagrams, but doable with perserverence.
While the Insteon Hub is easy very to add since it's a homekit device, adding the 30+ light switches etc is a chore since that must be done in the Insteon app not the Home app or by manually holding buttons on the devices which only worked half the time. Hopefully there will be a way around this in the future.
In regards to Insteon naming conventions compared to Apples...
Same Name:
Insteon Scene = Apple Scene
Insteon Room = Insteon Room
Different Name
Insteon Device = Apple Accessory
Insteon Schedule = Apple Automation
No Match
Insteon Zone = ?
Does Apple not have an equivealent to Zones? For instance an Insteon a Zone would be for instance "Downstairs", "Upstairs", "Basement", "Outside", etc. So pretty much a group of rooms (where is rooms are a group of local assecories). Theoretically I guess you could create an Apple Scene called "Downstairs" but a Zone (a group of local rooms) seems distinct from a Scene ( a group of various accessories) in my opinion.
So far Siri has worked quite well in general with Insteon and Home app on iOS 10. The main issue is that 9 out of 10 times the Home app shows "Not Responding" for all the many Insteon items in the house. If you tap on an item it will say updating and then it will properly show you it's status. Not sure if this is an Insteon issue or a Home app issue. The Insteon App doesn't appear to the have the same issue, so assuming it's an Apple issue unless Insteon needs to do an update to have its accessories show the proper status to the Home app?
Automation seems very limited and no way to combine multiple things. For instance, I can say turn outside lights at sunset (great). But say I want to have the lights turn off 6 hours after sunset, no way to do that. Or I can set a scene for when I come home, but if I come home during the daylight time, I would want different lights than if I came out after sunset. I don't see anyway to handle that common need.
Currently don't have another phone to test, but curious how multiple home users works. That is most all homes I assume have multiple people. So if you go out to the store and your partner stays home, you wouldn't want the house turning the lights off on them. But if you both leave the house you would want all the lights turning off. I see there is an invite people to your home option, but curious if then we setuping up geolocation automation, if it factors in the location of both people or not which is very important, like Nest does.
In the Home app on iPhone Favorite accessories on the main screen are all listed three to a row with unlimited rows, where is with Scenes it only shows 2 and you have to swipe left to see more scenes. I think scenes should all be listed, and if anything accessories should be swipe to see all if necessary.
There are no time since automation options. For instance with bathroom fan for instance, that get turned on by a switch and often forget to turn off since you want the room vented after a shower. Having an option in Home to say turn off this device after x minutes of being turned on, or if you wanted a light to turn off after a set amount of time.
Insteon scene switches are great, sadly, currently there is no way to associate a scene button on the wall with a homekit scene. You could do this via siri but not the actual wall switch, and while siri is great, all your guests to your home will be using the wall switches not siri in general to control things. This I assume is an Insteon issue however.
Would love to see a home app on Mac, even if just in the control center. At least you can control via siri on Mac, but no visual representation of the status of your devices. Of course an option to view and control online would be great but since Apple isn't strong on web services that may not come for quite some time and appear redudant to the common casual user.
That's my initial thoughts so far. Highlights being Apple Home needs zones, and Apple/Insteon need to resolve the Not Responding issue, automation needs to be able to combine multiple triggers, an automation for time since, and dealing with geolocation with multiple users.