NetDroid: summarizing network behavior of Android apps for network code maintenance

Network access is one of the most common features of Android applications. Statistics show that almost 80% of Android apps ask for network permission and thus may have some network-related features. Android apps may access multiple servers to retrieve or post various types of data, and the code to handle such network features often needs to change as a result of server API evolution or the content change of data transferred. Since various network code is used by multiple features, maintenance of network-related code is often difficult because the code may scatter in different places in the code base, and it may not be easy to predict the impact of a code change to the network behavior of an Android app. In this paper, we present an approach to statically summarize network behavior from the byte code of Android apps. Our approach is based on string taint analysis, and generates a summary of network requests by statically estimating the possible values of network API arguments. To evaluate our technique, we applied our technique to top 500 android apps from the official Google Play market, and the result shows that our approach is able to summarize network behavior for most apps efficiently (averagely less than 50 second for an app). Furthermore, we performed an empirical evaluation on 8 real-world maintenance tasks extracted from bug reports of open-source Android projects on Github. The empirical evaluation shows that our technique is effective in locating relevant network code.