Show HN: Undetectag, track stolen items with AirTag

34 pompidoo 39 5/15/2025, 3:46:26 PM undetectag.com ↗
I developed a device that turns an Airtag on and off at specific intervals. Current Airtags are detectable right away and cannot be used to track stolen property. That device allows you to hide an Airtag in your car, for example, and someone that steals your car will not be able to use some app to detect it. The Airtag will also not warn the thief of its presence. After some hours, the Airtag turns on again and you can find out its location. It’s not foolproof, as the timing has to be right, but still useful.

What do you think?

Comments (39)

wanderer2323 · 1h ago
You have also developed a device that allows people to use AirTags for stalking.
_QrE · 1h ago
This. Normal AirTags are just fine for tracking your stuff.

> "(thiefs use apps to locate AirTags around, and AirTags will warn the thief if an unknown AirTag is travelling with them, for example if they steal your car)"

The reason this was introduced is exactly because people used AirTags to stalk others. Advertising that your product turns that off is basically targeting that specific demographic.

Ajedi32 · 1h ago
That's true. But the advertised use case (tracking stolen items) is perfectly valid.
atoav · 11m ago
So if I invent a device that crushes orphrans, but I am advertising it as a nice decorative object for afluent art collectors I am morally totally protected from being called out for building an machine that people use to crush orphans?

Neat trick to avoid responsibility.

thebruce87m · 54m ago
> The reason this was introduced is exactly because people used AirTags to stalk others.

There were anti-stalking features from the start. It didn’t stop the media hysteria however.

pompidoo · 1h ago
As it's 4 hours off / 1 hour on, the device is not very suitable for stalking someone. Also once the AirTag is back on and the person starts moving, they will be alerted that the AirTag is tracking them.
schmichael · 33m ago
That’s perfect for finding out where someone lives. Drop it in their bag or jacket at a concert/bar/work/whatever-in-the-evening, and the place they’re likely at in 4 hours is their home.

Not trying to be creepy, I’m just trying to demonstrate how we all need to think like adversaries (eg creeps) when designing products.

fn-mote · 27m ago
You can probably find out where they live from knowing their name. This application is not a high level of stalking.
schmichael · 24m ago
The concert/bar example allows stalking without knowing someone’s name.
andygeorge · 8m ago
> not a high level of stalking

imo no level of stalking is appropriate. while this device might not do everything a stalker wants it to, it surely makes it easier for them

hangonhn · 29m ago
That's not true in all scenarios.

I once donated an infant car seat to a coworker but forgot I had put an AirTag on it. After she had taken it home, her iPhone told there was an unknown AirTag and she texted me. I apologized profusely and she wasn't bothered by it. Nonetheless had I been nefarious, I would have been able to get her home address.

cmeacham98 · 1h ago
> Events outside our control, such as Apple updating the firmware in the future to prevent the device from working, will not qualify for a refund.

I fully understand why you would want to do this, but as a consumer I would never buy this product with this clause.

pompidoo · 33m ago
I understand your point. In this case the price point makes this a bearable risk, especially to protect much more valuable items. A refund is only useful if only a certain % of people have issue or the company is big. Since this is my only product, an Airtag update that bricks the devices would just bankrupt the company and make me unable to refund most people as my margin is very low anyway.
dudeinjapan · 1h ago
A reasonable solution would be to get to buy the newer model half-off if this happens. Obviously the maker can’t just have his entire biz nuked with refunds if Apple happens to update firmware.
mulmen · 33m ago
I think you have your priorities wrong. Why should an unsustainable business be prioritized over consumer benefit?

Nobody has a right to a successful business but when consumers can trust their purchases they are more likely to make additional purchases.

_aavaa_ · 5m ago
The lack of trust in the purchase comes from Apple, not from this seller. It's apple that's reaching into your device and force updating the firmware without your consent.
hollow-moe · 1h ago
Very nice, you can also add "unsuspecting ex" on your homepage or something. These devices should be outright illegal, just remember where you put your keys. You shouldn't go get back your belongings from a thief anyways.
Ajedi32 · 1h ago
> You shouldn't go get back your belongings from a thief anyways.

And the police shouldn't either? Seems like knowing the location of your stolen property would help with getting it back in most cases.

1propionyl · 1h ago
In practice it does not. If you have had something with FindMy tracking stolen you may know what apartment block it's in, but not what unit.

Police won't or can't do anything if it could be in multiple units or would require any kind of warrant for the building as well as the specific unit you think it's in.

If you're "lucky" some might chaperone you knocking yourself, which itself is not something most want to entertain.

On account of police policy, AirTags are effectively useless for actually getting anything stolen back. You'll get more use out of them in filing your insurance claim if the theft of the item is covered under for example your homeowner's insurance policy.

ops · 31m ago
This depends on where you are. In Florida, the police will absolutely go get your stolen property if you give them an AirTag location.
Ajedi32 · 58m ago
That's only a problem if the stolen property is in an apartment and not a house or driveway. And even in the apartment case it could probably be used in combination with other evidence (if available) to obtain a warrant, though you're correct that in practice police don't often have the bandwidth to investigate property crimes to that degree.
dinkblam · 52m ago
> These devices should be outright illegal

why should protecting my belongings from thieves be illegal?

> You shouldn't go get back your belongings from a thief anyways.

you can also send the police to the thieves if you know where they are

seriously, there are like 10 stalkers worldwide but 2 billion thieves. most likely any stalking story was made up by thieves because they hate if people get their stuff back...

lostlogin · 32m ago
> seriously, there are like 10 stalkers worldwide

In the UK 1 in 7 has been stalked. Usually the victims are women or young people. The second link says that in the western world 2-15% of the population have been stalked.

https://www.ons.gov.uk/peoplepopulationandcommunity/crimeand...

https://pmc.ncbi.nlm.nih.gov/articles/PMC10515444/

InsideOutSanta · 37m ago
>why should protecting my belongings from thieves be illegal?

Making tracking devices illegal does not make it illegal to protect your belongings from thieves.

>there are like 10 stalkers worldwide

Given how many women I know who had issues with stalkers, all ten must live near me.

mulmen · 40m ago
> why should protecting my belongings from thieves be illegal?

A concealed tracker doesn’t protect you at all. It only aids in recovery.

> you can also send the police to the thieves if you know where they are

No, you can’t. The police do not recover stolen property based on an AirTag ping. They won’t lift a finger.

wat10000 · 39m ago
I try to remember where I put my cat but for some reason he's never in the place I remember.
pompidoo · 1h ago
The Airtag is mostly off and when back on will alert the person.
mousethatroared · 30m ago
Or kidnapped children
wepple · 39m ago
Problems: if the thief steals your item while the AirTag is on, they can find and disable it.

Have you experimented with a setup (more complicated to package) where you have two AirTags and alternately power one at a time? Could that bypass apples detection whilst also broadcasting location?

Edit: at sufficiently small time durations to run under apples detection radar, but for long enough to be picked up as a location

I don’t know how Apple detects the tracking; this would easily be solved by them.

pompidoo · 26m ago
Yes I think having 2 is a good strategy. I'm also considering offering different timings in the future.
cinntaile · 53m ago
Can the time interval be changed by the user or is it hardcoded? What are the limits if they can be changed?
pompidoo · 45m ago
hardcoded, but I'm thinking of offering different time intervals in the future
pimlottc · 1h ago
Wouldn't this also greatly reduce the reliability of tracking, especially in rural areas where there might not always be a Find My network device nearby?
subscribed · 25m ago
In rural areas you're always better off with gps+lte+LoRA tracker anyways.
pompidoo · 1h ago
Yes, unfortunately it would.
givinguflac · 1h ago
Very cool idea, and I love how compact it is!

My only feedback would be re: the site, specifically this part:

“ Airtag is a trademark registered by apple and we have nothing to do with apple.”

Might want to capitalize Apple; just a nitpick.

pompidoo · 1h ago
Good catch! Thank you I will correct it now.
mulmen · 44m ago
AirTags aren’t meant to get stolen items back. That just isn’t the use case. How does this compare to actual GPS trackers like https://monimoto.com/?
lostlogin · 26m ago
That device you link to is more expensive but would never alert the person being stalked, so I suppose that might justify the price.