Along with the release of iOS and macOS 10.15 13 Apple joined the app “Find friends” and “Find my phone” into one utility. The latter turns your Apple gadgets into a kind of Bluetooth beacons, allowing you to find your lost or stolen device even if it is not connected to mobile or Wi-Fi network.
This innovation was made possible through the use of Bluetooth Low Energy technology that requires so little energy that it can send signals with a fully discharged device for another one to two months. This signal catch other iPhone or iPad that are close to the lost gadget.
However, in all this there is one caveat. In order to find the lost device, the user need to have another Apple device tied to the same account. The only way to decipher the location of a missing iPhone, iPad or MacBook. To ensure privacy of user information is missing, the device sends a constantly changing key.