Almost everything people get wrong about AirTags comes from assuming there is a GPS receiver inside. There is not. Understanding what is actually in there explains the battery life, the price, the dead spots and the absence of a subscription, all at once.
What is inside
A Bluetooth Low Energy radio. A speaker. An Ultra Wideband radio. An accelerometer. A CR2032 coin cell. No GPS receiver, no cellular modem, and therefore no idea whatsoever where it is.
The mechanism, step by step
1. The tag shouts. It broadcasts a rotating, encrypted identifier every few seconds. The identifier changes so that the same tag cannot be followed by a third party across time — that rotation is the core of the privacy design.
2. A stranger's iPhone hears it. Any nearby Apple device — in a shop, on a bus, walking past your car — picks up that broadcast. Its owner is never told and never sees anything.
3. That phone reports. It attaches its own GPS position, encrypts the pair so that only you can read it, and sends it to Apple. Apple describes this as anonymous and encrypted, and efficient enough that the relaying phone's owner need not worry about battery life or data usage.
4. You open Find My. Apple hands you the encrypted report, your device decrypts it, and you see a pin and a timestamp.
That is the whole system. The tag is a beacon; the network is other people's phones.
Why this makes it free
There is no recurring cost for Apple to recover. The data that locates your AirTag was carried by somebody else's phone plan in increments too small to matter.
That is why there has never been an AirTag subscription, and why a subscription would be charging for something that costs Apple almost nothing — on a product whose purpose is making iPhones stickier.
Why it goes silent in a field
Same mechanism, inverted. No passing Apple device means no report. The tag is working perfectly and has nothing to tell you, for as long as nobody walks past.
This is not a limitation better hardware fixes. It is the design.
Precision Finding: the second radio
The Ultra Wideband radio does something different and much more local. When you are within roughly the same room, a UWB-capable iPhone can measure distance and direction to the tag precisely, and the Find My app turns that into an arrow and a distance that walks you to it.
Apple states the second-generation AirTag has 1.5 times the Precision Finding range of the original, plus a speaker 50% louder.
Two things follow. UWB only helps at close range — it is not how a lost AirTag across town is found. And it is first-party only: third-party Find My tags ride the same network but do not get the arrow.
The accelerometer, and what it is really for
The motion sensor exists mostly for safety rather than convenience. It is how the tag knows it is being carried while separated from its owner — which is what triggers the unwanted-tracking sound and the alerts on nearby phones.
It is also why a tag sitting still in a drawer behaves differently from one traveling in a stranger's bag.
The privacy design, which is better than people assume
Three properties worth knowing:
Rotating identifiers. The broadcast changes regularly, so a third party cannot follow a particular tag over time by listening.
End-to-end encryption. The relaying phone cannot read the report it submits, and Apple cannot read your tag's location either — only your own devices hold the key.
No data for the relayer. The stranger whose phone reported your tag learns nothing, and is not notified.
The flip side is the unwanted-tracking problem, which Apple addresses separately with alerts and sounds. Those protections are here.
The battery, and what Apple's figure means
Apple states that an AirTag works for more than a year on a standard replaceable battery, and that the figure is based on everyday average usage of playing sound and Precision Finding — with the footnote that battery life varies with usage, environmental conditions and replacement battery manufacturer.
Practically: ring it fifteen times a day and you will not get a year. Leave it in a suitcase and you will get more. Your iPhone tells you when it is low.
The physical specifications
Apple states the AirTag is rated IP67 — splash, water and dust resistant, tested under controlled laboratory conditions to a maximum depth of 1 meter for up to 30 minutes under IEC standard 60529 — and notes that resistance is not a permanent condition and may decrease with normal wear.
The battery is a user-replaceable CR2032 coin cell, which is the entire reason an AirTag has a running cost of about a dollar a year.
What all this means when you buy one
A clear-eyed summary: you are buying a beacon that borrows positions from strangers' phones. That is excellent where there are strangers and useless where there are not, it costs nothing to run because the data was never yours to pay for, and it tells you where something was rather than where it is.
For keys, bags and tools, that is the right product. For a vehicle or a roaming animal, it is the wrong category. That comparison is here.
