Have you tried to set up Find My iPhone (or Mac, or iPad) on your Apple device? I have, and I found a great lack of instruction or guidance on how the setup worked and what you were supposed to do to get it arranged. That's why this particular post from Mac Tips is my all time most useful Mac Tip ever! Miraz writes,
A lost iPhone, iPad or Mac can be traumatic on many levels. Find My iPhone at least takes a little of the stress out by allowing you to find devices, add a helpful message or even wipe them remotely. Find out how before you need to find your lost gadget.
image from apple.com