Use Android Device Manager Guest Mode to Find a Friend’s Phone
Android: If you are not using Android Device Manager to locate your lost phone, we highly recommend it . But what happens when you actually lose your phone? Thanks to the guest mode in the Android app, you can use a friend’s phone to find yours.
The Android Device Manager app lets you quickly find, block, or erase data from your other devices. However, you can also use guest mode to let someone else quickly log in and find their device. This makes it much easier to help a friend find their phone, as the only alternative is to log into your account from a laptop, which may not be readily available. In any case, if you are not using ADM to track your phone in an emergency, it is highly recommended that you set it up now.
Android Device Manager | Google play store