Here is a compact Bluetooth device that helps you track and find keys, wallet, backpack, pets, and everything in between. It is about the size of a coin and has an app for iOS, Android, and Windows. Chipolo has a range of 200 feet and 6 months battery life.
Chipolo not only helps you find your misplaced items, but it also lets you know when you are about to leave valuable items behind. Simply attach it to anything, and you are set. Did we mention that it can be a selfie remote?[where to get it]