Portable GPS & Battery Cradle for iPod touch. High-sensitivity GPS Receiver works with most apps that require GPS information. ? Rechargeable Battery powers the GPS when on the go so you don?t use up the iPod battery. When not in GPS mode the battery can recharge the iPod. ? Built-in powered speaker amplifies spoken directions in turn-by-turn navigation apps. ? Built-in Microphone allows the use of voice memo and communications apps. ? Includes car windshield mount for use in cars and on boat windscreens. ? Works anywhere in the world.