Every so often I've been asked if ProximityLock and ProximityShortcuts apps support any other devices aside from the iPhone and Watch. And my answer: yes they do but your mileage may vary.
iPhone and Apple Watch are a safe bet. They are linked to the same Apple account (hence almost impossible to spoof the mac address if it makes sense). And usually they are either in your pocket or on your wrist - the best way to track proximity. With other devices I simply can't guarantee anything - they may work well or may not - headphones, fitness bracelets, etc. Many devices just simply don't transmit BLE beacons unless they are in pairing mode. Except, of course, the TVs - they are constantly screaming that they are here and you can see what TVs your neighbours have.
So I had some time to dig deeper and started to look if there are special bluetooth beacons out there. And I found an interesting one. It can be customized: you can set signal strength, beacon interval, and beacon name of course. Just to be clear, it's not an ad, it just caught my attention.
Feasycom FSC-BP108B IP67 BLE Beacon
SSD is for size reference
It is actually a keyfob, relatively small and light (~14 grams). I'm not sure yet if it is that convenient to use as a proximity device. But I guess it is a matter of habit - you just need to keep it in your pocket with you.
I've been testing it for a week already and it works well, the signal is stable, and it doesn't stop transmitting beacons all of a sudden. It must be configured to transmit a beacon at least every 500ms or a bit more often to reliably detect signal degradation when you go away.
I'll continue to test it further. But if you have a MacBook, for example, but don't have an iPhone or Apple Watch, you can try this tiny device instead.
PS: Now I'm thinking about whether I should start working on a Windows version of the app.