A Study on the Energy Consumption of Android App Development Approaches

Mobile devices have become ubiquitous in the recent years, but the complaints about energy consumption are almost universal. On Android, the developer can choose among several different approaches to develop an app. In this paper, we investigate the impact of some of the most popular development approaches on the energy consumption of Android apps. Our study uses a testbed of 33 different benchmarks and 3 applications on 5 different devices to compare the energy efficiency and performance of the most commonly used approaches to develop apps on Android: Java, JavaScript, and C/C++ (through the NDK tools). In our experiments, Javascript was more energy-efficient in 75% of all benchmarks, while their Java counterparts consume up to 36.27x more energy (median of 1.97x). On the other hand, both Java and C++ outperformed JavaScript in most of the benchmarks. Based on these results, four Java applications were re-engineered to use a combination of Java and either JavaScript or C/C++ functions. For one of the apps, the hybrid solution using Java and C++ spent 10x less time and almost 100x less energy than a pure Java solution. The results were not uniform, however. For another app, when we restructured its implementation so as to minimize cross-language method invocations, the hybrid solution using Java and C++ took 8% longer to execute and consumed 11% more energy than a hybrid solution using Java and JavaScript. Since most Android apps are written solely in Java, the results of this study indicate that leveraging a combination of approaches may lead to non-negligible improvements in energy-efficiency and performance.