Amber is available in multiple colors to match your Apple Watch. It has a USB port on the back which can be used to connect the iPhone and Bluetooth functionality which lets it notify you of battery charge, software updates, temperature changes, charge and discharge cycles, battery health, and location.
ClearGrass notes that Amber's circuitry is designed to charge devices directly when plugged into the wall in order to save battery cycle life.
We improved Amber’s circuitry so that when it’s connected to a power source, Amber will continue to charge your Apple Watch, iPhone, and Amber itself directly through the external power supply. By directing the incoming electric current flow outward, Amber effectively saves its battery cycle life. And when Amber itself runs out of charge, it simply functions as a normal charger and powers devices immediately.
Amber aims to ship in time for Christmas. You can pledge $55 for one of the first units at the link below...