If you just sign in to iCloud on your friend's iPhone browser, you'll be asked to enter a 6-digit passcode (a definite problem if your device is lost). The Help a Friend feature bypasses the two-factor authentication.

Follow the steps below and use the Help a Friend feature within the Find My app.

How to Find Someone’s iPhone: Important Notes Let's learn how to track an iPhone using your friend's iPhone.

The Find My app allows you to help a friend find their iPhone, since it now cleverly combines the Find My iPhone and Find My Friends functions. While it is most commonly used to locate your own devices, you can also find someone else’s iPhone using this feature. The iPhone Find My app is a great tool to find a misplaced, lost, or stolen iPhone.

With the Help a Friend feature, you can track and ping the lost device, as well as enable Lost Mode to protect your data until the lost iPhone is recovered.

Use the Help a Friend feature within the Find My app to help someone else locate their iPhone.

How to track an iphone