Instead of using conventional presence sensors as inputs for automated power management, the proposed solution utilizes a network of wireless power outlets and monitors the variations of the signal strength indicator used for the communication between them.
A wireless network presence detector element 214 can be coupled to the wireless network 208.The IP based format can provide an efficient method for signaling presence and availability information between the VoIP network 308 and the presence management network 306.

No need for complex tech jargon, we're here to simplify and make room-level presence detection accessible for all. We'll explore how you can seamlessly track presence in different rooms, providing valuable data for your home automation setu...

Webthings network presence detection. Using this add-on, devices on your local network can be added as a 'thing' in the Candle controller. Automations can then respond to their presence.
Et voila - reliable presence detection, or as reliable as I need. I had read that iPhones in particular were tricky for this as they go into a low power mode, but the setup as described has no trouble keeping track of the status of Apple devices just as well as android.