My sister tends to lose her phone every once-in-a-while. When we were taking an evening stroll with our friends, we got to our friends house, and about an hour later, she feels her pocket for her phone, and her eyes widen. I have seen this happen many-a-time, so I simply get out my phone and use FindMyiPhone. With our trusty adult chaperone, we set off, retracing our steps, trying to find the missing phone in the pitch black. I was convinced, because we were in a not-so-nice part of town, that it was done for, bye-bye iPhone. But, we used FindMyiPhone , and found that it was right where we were walking. I still panicked, because sometimes FindMyiPhone can say your phone is in one place, then 10 seconds later say it's 18 miles away. We used the "sound" feature and could hear it from half a block away. We found it unharmed.
A few months later, my mother lost her old iPod on a road trip. I used FindMyiPhone, and it said "locating"... But it just kept saying that. My best guess to why this is is that it was very old, too old to track. This iPod was not touch screen and only played music.
I've also heard complaints that FindMyiPhone doesn't work when the device is turned off, which I think sounds SO frustrating. Please fix this, otherwise, FindMyiPhone is a lifesaver!