The utility of a smartphone is limited by its battery capacity and the ability of its hardware and software to efficiently use the device’s battery. To properly characterize the energy consumption of an app and identify energy defects, it is critical that apps are properly tested, i.e., analyzed dynamically to assess the app’s energy properties. However, currently there is a lack of testing tools for evaluating the energy properties of apps. We present COBWEB, a search-based energy testing technique for Android.