Homey by Athom
The Homey has bluetooth wireless technology on board. With this you could, for example, link a wireless speaker. In addition, there are also some sensors on the market. Unfortunately, the Homey does not yet actively use this, so this protocol cannot be used properly yet.
What the Homey has implemented nicely is BT tracking. You can use this to determine whether you are at home or away.
As a BT tracker I use a Tile but any BT tracker should work. This works very well because as soon as the tracker comes close to the Homey (30 meters), the Homey sees it and knows that I am home. You should not forget the tracker of course :)
In the first generation of the Homey there was support for NFC. NFC (Narrow Field Communication) is a radio protocol with a limited range. You use a tag to communicate with. Such a tag can be the size of a euro coin and is very thin. It is often also built into your phone. Unfortunately Athom has decided to remove this NFC from the new Homey (v2). This can no longer be used. Athom gives the reason that not many users did something with this.