Does the Philips Hue Secure Contact Sensor work with HomeKit, Alexa, and Google Home?
The Hue Secure contact sensor watches a door or window and needs a Hue Bridge.
It is a Zigbee sensor that runs on a CR2 battery. It suits Home Assistant users, with native support through Zigbee. HomeKit, Google Home, Alexa and SmartThings users reach it through an integration (Zigbee).
How the device gets into the platform on this route. The headline is the best route: local before cloud, direct before bridged, core before community. The methodology page lists every level.