On Tuesday, along with a handful of other updates, Apple finally introduced one of its most long-rumored products, AirTags. The idea is really quite simple--you attach an AirTag, which is a small round disc-shaped tracking device, to something you might lose. For example, a set of keys.

Then, in the event you can't remember where you left them, you can use the Find My app on your iPhone to tell the AirTag to chirp at you using the internal speaker. The app will also direct you to the AirTag using the iPhone's Ultra Wideband chip, known as U1. 

If, however, you left something further away, the beauty of AirTags is that they use the Find My network so you can still find them. If you accidentally drop your keys while you're in the grocery store, the AirTag will still send its location back to you by emitting Bluetooth Low Energy that will ping nearby iPhones, which then transmit the location to iCloud. 

The whole thing is pretty incredible, but there is a potential problem. Two, actually. Both relate to the idea of creating a product designed entirely for the purpose of being tracked. That's something that has long gone against Apple's core value of privacy. In fact, the idea that you can have tracking in a way that protects privacy has been a complicated issue.

The first problem is figuring out how to use a network of iPhones to pass along the location of an AirTag while still protecting privacy. It turns out this was probably the easier of the two problems to solve.

Here's how Apple explains it:

Your AirTag sends out a secure Bluetooth signal that can be detected by nearby devices in the Find My network. These devices send the location of your AirTag to iCloud--then you can go to the Find My app and see it on a map. The whole process is anonymous and encrypted to protect your privacy. And itʼs efficient, so thereʼs no need to worry about battery life or data usage.

Considering there are one billion iPhones in active use, there's a pretty good chance that at least one will pass by your lost AirTag. That's a really brilliant solution.

But, what if someone decided to use an AirTag to track a person? That's an entirely different problem.

It's certainly not an unforeseeable possibility, and the reason we know this--beyond just common sense--is that Apple foresaw exactly that. And it designed AirTags to tell you when one is close by that isn't connected to your Apple ID. 

Again, here's Apple's explanation of how it works:

AirTag is designed to discourage unwanted tracking. If someone else's AirTag finds its way into your stuff, your iPhone will notice it's traveling with you and send you an alert. After a while, if you still haven't found it, the AirTag will start playing a sound to let you know it's there.

Of course, if you happen to be with a friend who has an AirTag, or on a train with a whole bunch of people with AirTag, don't worry. These alerts are triggered only when an AirTag is separated from its owner.

So, if someone dropped one in your bag while you weren't looking, or tried to attach one to your vehicle, your iPhone would tell you that there's an unknown AirTag nearby. After an AirTag has been separated from its owner for a while, it will start to chirp. 

For a company as focused on protecting your information as Apple is, it makes sense that it wouldn't want AirTags to become a privacy issue. In fact, I think it's fair to say Apple just demonstrated you really can build products designed to be tracked that still protect user privacy.