A Battery-Aware Energy-Efficient Android Phone with Bayesian Networks

Recently, as the number of smart phone users increases rapidly, various applications using GPS become widespread. Because GPS sensor has drawback that consumes too much energy, we have to decrease the unnecessary usage of GPS receiver at indoors to reduce the energy consumption. Most of previous works focused on how to reduce the frequency or the period to use GPS. In this paper, we propose a method to save battery using Bayesian network inference with built-in sensors in a smart phone to get location information efficiently. In order to show the usefulness of the proposed method, we have developed an application in Android platform and performed experiments to evaluate Bayesian networks. Experimental results on real datasets has shown that it is possible to predict user´s location at either indoor or outdoor. On weekday, accuracy is 77% which is higher than on weekend, 68%. Analysis implies that user lifestyle and life pattern in weekday have less changes than that in weekend. In terms of battery efficiency, active person and inactive person save energy of about 5% and 3% per hour, respectively.