In iOS 15, Apple added separation alerts to the Find My app that notify you when you leave an AirTag or other Apple device behind. Separation alerts also support Find My-enabled third-party accessories.
Called “Notify when left behind,” the new Find My separation alerts or notifications will notify you every time you are separated from your personal item or Apple device in an unfamiliar location, which can be very helpful – both when traveling and in everyday life. function automatically sets your home as a trusted location (a place where you often leave your items and don't want to be notified every time - your home?!), so you'll need to add your home address to your contact card in the Contacts app before enabling the feature.
Notify when left behind: How to activate the function in iOS 15
The following steps will guide you through the process of setting up disconnection alerts.
- Start the Find My app on your iPhone.
- Select the Devices or Items tab and tap the device you want to set up notifications for.
- Tap Notify when left behind.

- Activate the switch for the feature.

- Under Notify me except here, tap New location to set a trusted location where you don't want to receive notifications.
On the Add Location map screen, you can search for an address or enter one in the input field. You can set the radius of the ring geofence for your trusted location by dragging the blue dot or using the Small, Medium or Large options at the bottom. Now tap Done.

If there are no more location exceptions you want to add, tap "Done" in the top right to complete the configuration. Now, the next time you leave your AirTag or another Apple device in a public place, you will receive a notification that informs you in time and gives you the opportunity to turn back. But be careful: These types of notifications require an iPhone, so you should make sure you don't leave your iPhone behind. Apple may also expand the feature to include the iPhone with the Apple Watch at some point. (Photo by hadrian / Bigstockphoto)