I am running Philips Hue and Homekit for years now. I always had trouble with this combo. Philips Hue has native Homekit support. This basically means that every device (Philips Hue stuff only) is automatically exposed to Apple's Homekit ecosystem and appears in the Home app. This is true for lights, sensors and switches (basically all that Homekit is able to use properly).

The Problem

It sometimes occurred that Hue devices did not respond or were displayed as unavailable or "Updating". Even worse: devices I added to the Hue bridge didn't even appear in the Homekit. You can basically add any Zigbee device to the Hue bridge (it's just a Zigbee bridge), or let's say: any device that the Hue app supports, which is lights, motion sensors and switches.

Here is a sample on how this mess looks like:

Running "unsupported" devices on a Hue bridge

If you want to integrate those unsupported stuff in Homekit using the Hue bridge, there is basically only one satisfying way: Homebridge and the Hue plugin.

Usually you would configure Homebridge and the plugin to not expose natively exposed stuff via the Hue bridge itself like the LED strips from Lidl. They actually then work very reliable - better than the native Hue devices.

Remove the bridge!

Due to the fact that my problems with the Hue integration got worse, I decided to remove the Hue bridge from Apple Homekit entirely and only use Homebridge as a bridge instead. You only then have to make sure the plugin exposes everything now, so the Homebridge Hue configuration part would look like this:

{
            "name": "Hue",
            "anyOn": true,
            "effects": true,
            "groups": true,
            "lights": true,
            "linkButton": true,
            "nativeHomeKitLights": false,
            "nativeHomeKitSensors": false,
            "resource": true,
            "scenes": true,
            "sensors": true,
            "excludeSensorTypes": [
                "CLIP",
                "Geofence",
                "Daylight"
            ],
            "hueDimmerRepeat": false,
            "users": {
                "xx": "xx"
            },
            "platform": "Hue"
        }

The key settings here are nativeHomeKitLights and nativeHomeKitSensors. The latter also exposes the dimmer switches etc. Make sure you also have sensors set to true. There is a special setting hueDimmerRepeat for those dimmer switches (old and new) here which I don't use in Homekit. If you want to use the dimming function set this value to true, too.

Result

Since I changed to Homebridge, everything is stable now. Again: add your stuff in the Hue app (lights and switches) but do not add the Hue bridge to your home. Using it in the Hue app still allows you to use entertainment areas and the Hue sync app, which I love!

And if this isn't enough: Homebridge also allows me to use other stuff directly in Homekit and with Siri which are "dumb" ceiling fans (using a Broadlink IR plugin), my MiHome Robot Vacuum and also my DYI WLED LED strips 

Besides that I think that Philips Hue is too expensive for what you get and there are tons of cheaper alternatives.

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