I am having the same issues here. We had an iphone 4 and with the cellular data OFF, we were still able to locate the phone. With the new Iphone6, it is not working and for some reason, it is relying on the family App (and cellular data) to work. If this is the case, this program becomes useless as Find my iphone can also do this. Why did AT&T change this on the iPhone 6, as if this is the case, I am cancelling this service.