It is a type of tracker but not GPS, it connects to your phone via Bluetooth, but if you are out of range it will connect to anyones iPhone and through the network tell you where it is, without anyone knowing it. If found it can also be connected to an Android or iPhone and a message will pop up with whatever info you have added to it like a phone number and 'call me' message. I think Apple are thinking everybody out there is a really nice person and will return it, but if an item i.e. a backpack. is stolen then the tag will just be removed or disabled by removing the battery. The weird thing is if you have a air tag in a car for example and your car is stolen, if the bastard that has stolen it has an iPhone they will get a message that an air tag is there and will even let them play a tune on it to find it, sort of defeats having one I think. Tapping lost on your phone may change this, more testing to be done.