How to Scan For Bluetooth Trackers On Android
Recently, I came to know that Air Tags are used by stalkers, and any iPhone relay information from any Air Tag. I think the Apple botnet is evil, so I wrote this article.
At time of writing, I do not know how to solve stalking in general. I must understand the society more before I can answer this social problem. (If you are interested in a deep investigation into stalkerware, I recommend reading the #FuckStalkerware series from maia. I do not endorse its view on culture.)
For now, here is a technical workaround: you can detect some bluetooth trackers (including Air Tag) on Android.
To do that, install AirGuard from F-Droid, and the app should teach you how to scan for a limited selection of bluetooth-based trackers.
Musings
AirGuard comes from The Secure Mobile Networking Lab.
While reading the source code, it seems like AirGuard can only know if a tracker is connected to its owner when the tracker is made by Apple, Chipolo or Samsung.
The source code also mentioned some terms that I found in this paper1. Within, PREMATURE/OVERMATURE_OFFLINE made me think of firebugs that regulate glowing based on an internal timer. Maybe bluetooth trackers do glow like firebugs in 2.4GHz. I will see that sometime in the future. For now, have a table from the paper.
| Bits 5-7 | Name | Description |
|---|---|---|
| 001 | (1) Premature Offline Mode | the tag has recently been disconnected |
| 010 | (2) Offline Mode | the tag has remained disconnected for over 15 minutes |
| 011 | (3) Overmature Offline Mode | the tag has stayed in Offline Mode for over 24 |
| 100 | (4) Paired with one device | the tag is paired to a device |
| 101 | (5) Connected to one device | the tag is connected to a device |
| 110 | (6) Connected to two devices | the tag is connected to two devices |