Demystifying energy usage in smartphones

In this paper, we presented our recent characterization and analysis on the power consumption of smartphone radio components, including Wi-Fi, GPS and cellular (3G/4G) modules. Different from previous research that focused on the properties of single module under a limited number of usage scenarios, our works are performed on the statistically selected representative Apps with four generations of Samsung Galaxy series smartphones. We found that over the four characterized generations, the average power consumption of the smartphones with a connected Wi-Fi network on the selected Apps increases about 38.20%, indicating more and more energy-hungry designs. However, the raising of the power consumption is not mainly from the radio modules as the power efficiency of the Wi-Fi module indeed improves by about 21%. The 4G module consumes about 15.13% more power compared to the latest 3G module. But the power efficiency of 3G module improves by averagely 15.17% over the four generations. The GPS module also shows 25.80% power consumption improvement over the generations. We also show that the characterized power results can be combined with the real user traces for detailed daily energy usage estimation. Our research established an ethological and evolutionary power consumption trend of smartphones, which will guide the power optimization in the next-generation smartphone design.