Apple iCloud and the Find My iPhone app are used to track an iPhone, and both have the ability to find the iPhone's location. By using the Lost Mode feature, iCloud or Find My Phone pinpoints the iPhone's location and where it's been on a map.
While the iPhone is in Lost Mode, it keeps track of where it has been in the preceding 24 hours and continues to track it until it is found. If the iPhone is lost, the device's owner locks it through the Lost Mode feature and sends a message to the device with a contact number. This feature also allows an iPhone owner to erase all content on the device to protect personal or sensitive information stored on it.