Not sure where to start with starter Kit and how to measure energy consumption? Here is a good video guide made by David L. Jones from EEVblog.
EEVblog is an electronics engineering video blog showing how to test various electronics design products in an unique and enthusiastic way. In this video, David tested how Tiny Gecko starter kit makes it possible to use only 20nA energy consumption in standby mode. He also demonstrated how to use Energy Micro’s free software, Simplicity Studio, for advanced energy monitoring.