There appears to be a HomeKit issue affecting RGB and RGBW bulbs exposed to HomeKit. This occurs with both Zigbee bulbs and virtual RGBW bulbs, so it doesn’t seem to be device-specific.
To reproduce the issue:
Expose a physical or virtual RGB/RGBW bulb to HomeKit.
In the Apple Home app, set the bulb to any color (e.g., green).
Completely exit the Home app. (To be certain, you can reboot the iPhone.)
Reopen the Home app and check the displayed color.
You'll notice that the Home app shows the bulb as “soft white,” even though the actual bulb and the Hubitat UI still correctly reflect the selected color (e.g., green).
This bug makes it difficult to verify a bulb’s current color and prevents color state from properly syncing across devices.
Hopefully the developers can take a closer look at this issue.
If it’s a bug, it’s on the Apple Home side of things. I have Philips Hue RGBW bulbs connected to a Philips Hue Bridge, and integrated directly with Apple Home via the Hue Bridge’s HomeKit integration. They behave exactly the same in Apple Home as what has been described above in the OP.
I changed a bulb to green via Apple Home, then closed the Apple Home app and reopened it - the bulb is still green but Apple Home shows it as Soft White.
I have a Matter over WiFi RGBW night light. That device is integrated with Apple Home via Matter. It is also integrated with Hubitat and Home Assistant via Matter. Both Hubitat and Home Assistant show the correct color of that light (red), but Apple Home appears to be confused and shows the light as a shade of blue.
Have you only tested this with Hue, or have you tried other HomeKit products as well? For example, I've tested this with the Eve Flare and LIFX bulbs, and neither shows this issue.
What’s most likely happening is that both Hubitat and Hue have a broken or incomplete implementation of HomeKit that needs to be fixed.
Also, Hubitat’s integration here is HomeKit, not Matter, which is why I'm comparing it specifically to other HomeKit implementations.
And this isn’t the only case where Hubitat had an issue with HomeKit implementation. For example, I started another thread about Hubitat’s issue with dimmers and HomeKit, where HomeKit did not remember dim levels. It took a while, but Hubitat did eventually fix that issue. Lutron Caseta actually has the same problem, and many Caseta users think it’s a HomeKit bug, not realizing that Lutron’s HomeKit implementation is the one that’s broken. Here’s that thread for reference:
If the developers need me to run any more tests, I’m more than happy to help.
It looks like some work was done on a recent build to fix the issue. Thanks for working on fixing it!
However, it seems like there may be some more testing needed. While the bulbs now report the correct color on HomeKit (excellent), when clicking on the bulb in the Apple Home app, it frequently says "No Response". This makes it difficult to adjust the color within the Apple Home app.
Thank you again to the devs for their hard work. Hopefully, they can completely squash this bug.
