Technology / 

23 Jun 2022

Notes on Bluetooth trackers and beacons

Notes taken while researching the basics of Bluetooth / BLE trackers and beacons, in mid-2022.


Presence Detection for Home Automation

Milwaukee “Tick” Asset Trackers

I got a free one of these to play around with, so naturally, I played around with it.

Linux Tools

$ bluetoothctl [bluetooth]# menu scan [bluetooth]# clear SetDiscoveryFilter success [bluetooth] back [bluetooth] scan on

Bettercap Sniffing Tool on Linux


Seems like a neat technology, but I’m not sure I have any immediate use for it right now. Apple’s Airtags apparently use a form of BLE, but the tags (when paired) don’t just bleat out the same code each time, they use some sort of psuedo-random rolling code system, where only Apple knows the seed value. This prevents anyone with an ESP32 from being able to track you every time you pass a fixed point in space, which would otherwise be trivial. From what I can tell, Tile trackers do the same or a very similar thing, but the cheaper tags used for tracking tools, managing inventory, etc. don’t — they just spit out the same information in response to every inquiry, basically like a self-powered RFID chip.

An interesting tool to keep in the toolbox, though. It would definitely be good if you were trying to keep track of loaner devices on a temporary basis, e.g. if you wanted to hand out some sort of hardware tracker device (boat race, orienteering, geocaching, whatever) and make sure you got them back, or wanted to be able to automatically do ‘check-ins’ as people pass specific points.