How can I find my iPhone without using the poor app ''Find My (Device).''

The feature is already there and has been available for almost 2 years. It’s called the Find My Network, and it uses crowd-sourced location detection. All you need to do is to leave Bluetooth enabled on your phone. And it even works if your phone is powered off.

FindMy is not designed to always get the device back. It can locate your device in the internet when it pops up and impose a usage-lock as well as erase-remotely. Both protect your privacy by making the device contents inaccessible.

If you are prone to losing your device, buy "loss/theft" insurance that provides full replacement ($3000 MBPs are in this category, $400 iPhones are not always).

If your iPhone, iPad, or iPod touch is lost or stolen