Abstract
Smartphones are becoming increasingly intertwined with people's daily lives. However, various hardware components of smartphones, such as CPU, GPS, screen and wireless interfaces, can easily run out of the battery's power. Therefore, power consumption has become the bottleneck for smartphones' prosperity. In order to reduce energy consumption of smartphones and extend the lifetime of battery, we develop an energy management system based on Android operating system, called Phone Joule, in this work. It switches between GPRS and Wi-Fi wireless networks, monitors and manages the energy consumption of smartphone in an intelligent manner. Six different power-saving modes are provided for users to easily manage the power consumption of their smartphones. Furthermore, the status of the smartphone, such as battery information and usage of CPU and memory, can be retrieved in real time.