Battmon is a simple Android Wear app that allows you to monitor your phone or tablet's battery. It displays remaining charge, the device's current power source, and the battery's current, voltage, and temperature. It's optimized for both round and square displays, and includes a power-efficient Ambient mode.

Full source available at https://github.com/karmeleon/battmon

LG G Watch R device frame by Daniele Bonaldo (https://github.com/danybony/wear-device-frames)
LG G Watch device frame by Cyril Mottier (http://cyrilmottier.com/2014/07/31/android-wear-flat-device-frame/)
Both frames used under a CC By licence (https://creativecommons.org/licenses/by/3.0/)