It is a nifty little tool to find your lost or stolen iPhone, iPad, iPod touch, or Mac using another iOS device with the intuitive app installed on it. The app not only helps locate your device, but also protects data on it.
Just install the free app on your iOS device, launch it and sign in with your Apple user ID. Find My iPhone app uses a map to locate your missing device. Other functions of the app include playing a sound, display a message, remote lock your device and erase all data on it.
iOS devices running iOS 6, feature Lost Mode; wherein it locks the missing device with a 4-digit passcode and displays the contact number right on the lock screen. While in Lost Mode, the device is capable of tracking and displaying its recent location history, when you login to your Find My App account with your registered Apple ID. Just make sure that Find My iPhone feature is enabled in the iCloud settings on your device for you to locate it with the app.