One charge for one week: Hype or reality?

For mobile devices, battery energy is the most precious resource. In the last decade, researchers have proposed various energy saving strategies from the system level to the hardware component level. In this paper, we explore how close to one week a smart phone running off of a single battery can last under normal usage. We first developed a battery lifetime prediction model that considers the influence of both user behavior and hardware components. Through experiments we analyzed the assumptions and the accuracy of the prediction model. We discussed the error rate of the estimated applications' power as well as its influence on the battery lifetime prediction. To analyze the impact generated by user behavior, we classify users into six types based on their application usage pattern. The theoretical battery life and potential extended battery time for each user type, with and without hardware improvement, have been illustrated. For example, compared with the original 66h (2.75 days) for users who rarely use their smartphone, we found that the battery life can be extended to 147h (more than 6 days) when we only maintain applications in the top three commonly used categories. Finally, several aspects, such as sleep frequency and background applications, that may affect prediction results are discussed.