Whether you want to track your friend's misplaced iPhone to help him locate it using the Find My iPhone feature or use a third-party app like Trusted Contacts to request your friend's location, you can track the iPhone from an Android phone. Apps such as Find My Friends for Android phones do not cross over to the iOS platform, so creative measures are needed to determine a location and perform any real-time location tracking. Sharing a static location is the easiest method of voluntary tracking, but any hands-on tracking requires app assistance.
Find My iPhone
The Find My iPhone service locates only Mac computers and iOS mobile devices that are misplaced, lost or stolen, and it works through the owner's iCloud account. You can track a friend's iPhone from an Android phone by logging in to a browser on the Android phone and going to iCloud.com. You or your friend must log in to iCloud with the phone owner's credentials. You can't track the phone if you don't have the account name and password for the iCloud account. Also, The Find My iPhone feature must be activated on the iPhone.
Google has removed the barriers to tracking across platforms with its Trusted Contacts program. The app enables you to track an iPhone from an Android device. It acts like a friend locator and is a replacement option for the popular iOS Find My Friends app when you want to include Android and iPhone users in the same group. Other third-party apps exist as well for tracking across platforms, but the Google Trusted Contacts program works with your existing Google account. Getting other users to link up is also easier because they are more likely to have an existing Gmail account or another Google-based account. Using a different third-party app means each user must set up a new account to join the tracking pool.
Tracking another person's phone should only be done with their knowledge and permission. Consideration for the user's privacy is of the utmost importance. A program like Trusted Contacts is a good choice because it requires the approval of other users to activate tracking. Users may forget to turn this feature off, however, and you should only track them when they want tracking to be enabled. Asking politely through a text message or phone call is a prudent practice. Also, protect your own privacy by turning off the tracking capabilities of your phone when you don't want tracking to be enabled.