Detecting Apple AirTag using BLE

neliss · April 12, 2022, 7:38pm

I am trying to detect presence of an Apple AirTag using BLE.
So far I haven’t been able to distinguish it from the 100+ BLE devices which I am detecting using the ESP32.
Has anyone been able to successfully detect it?
Is there any specific messaging format used by Apple which can be used to identify one?

DigiH · April 13, 2022, 12:15am

Hi @neliss, while I don’t have any AirTags myself and don’t know how they might advertise themselves, the following link shows that others are interested in them as well, and seem to already have more understanding of the requirements needed to possibly add a decoder for OMG in the future

github.com/theengs/decoder

Give decoders access to the device's Bluetooth address

opened 07:16PM - 06 Mar 22 UTC

koenvervloesem

**Is your feature request related to a problem? Please describe.** I'd like t…o implement a decoder for AirTag advertisements. The public key advertised by an AirTag is [partly encoded in the device's Bluetooth address](https://adamcatley.com/AirTag.html#advertising-data). So the decoder should have access to this address. **Describe the solution you'd like** A function `device_address` that returns a hex string of the Bluetooth address, e.g. `de479e575f8b`. **Describe alternatives you've considered** None **Additional context** I think I'll also need some kind of concatenation function for hex strings. See https://github.com/koenvervloesem/openhaystack-zephyr/blob/main/modules/openhaystack/src/openhaystack.c for how the public key is encoded. The first six bytes of the public key are encoded in the Bluetooth address, then come some bytes encoded in the manufacturer data.