The two-location test
Run a Bluetooth scan at home and note what you see. Then run one somewhere genuinely different, a different neighbourhood, a shop, a workplace.
Anything that appears in both lists is travelling with you. That is a small set, and it will mostly be your own devices and those of people you were with.
Repeat it a third time if something persists. Coincidence twice is plausible; three times is not.
Where trackers are actually placed
On a vehicle: inside the rear bumper, the wheel arches, under a seat, in the boot lining, inside the fuel flap, in the glovebox.
On a person: bag linings and rarely-used inner pockets, coat hems where the lining has a gap, the inside of a laptop sleeve, a child’s school bag.
In your belongings: taped inside a case, slid into a wallet card slot, in a jacket you rarely wear.
Signs that are not proof
A device with no name is not evidence. Privacy-preserving identifier rotation is standard on iPhones and modern accessories.
A device that is only ever present at home is almost certainly a neighbour’s.
Battery drain, phone heat and strange noises are not indicators of Bluetooth tracking, whatever the internet says.
If you find something
Do not confront anyone. Do not destroy the device.
Photograph it where it is, then contact the police. An AirTag’s serial number can be linked to the account that registered it, which is the single most useful piece of evidence available.
In the United States: National Domestic Violence Hotline, 1-800-799-7233. In the UK: National Domestic Abuse Helpline, 0808 2000 247. If you are in immediate danger, call your emergency number.
If there is any possibility this involves someone who has been controlling or abusive, speak to a specialist service before removing anything. Advocates deal with exactly this situation regularly and can advise on the safest sequence.
More on identifying devices
The rest of the material on working out what is broadcasting around you.
- How to scan a room for hidden Bluetooth devices, Method
- Reading Bluetooth signal strength (RSSI), Reference
- An unknown Bluetooth device is showing up. What is it?, Identify
- Save the devices you care about, My Devices tab
- How to find a lost Nintendo Switch or Joy-Con, About 20 hours on a Joy-Con
- Bluetooth hub, the complete list
Common questions
Can an app tell me for certain that I am being tracked?
No app can tell you who placed a device or why. What a scan can establish is a fact: whether a particular device is present in more than one location you have been in. That fact is what makes the difference between worry and evidence.
Do trackers work if I turn off my phone’s Bluetooth?
A tracker broadcasts independently of your phone. Turning your Bluetooth off stops you detecting it, it does not stop it working.
Is it legal to track someone with an AirTag?
Placing a tracker on a person or their property without consent is illegal in many jurisdictions and is treated as stalking in a growing number of them. If you find one, that is a matter for the police rather than for you to resolve directly.
In the app: The scan shows every nearby device with its name, battery and live signal strength. Read about Bluetooth Scanner.