An Android Application Risk Evaluation Framework Based on Minimum Permission Set Identification Android utilizes a security mechanism that requires apps to request permission for accessing sensitive user data, e.g., contacts and SMSs, or certain system features, e.g., camera and Internet access. However, Android apps tend to be overprivileged, i.e., they often request more permissions than necessary. This raises the security problem of overprivilege. To alleviate the overprivilege problem, this paper proposes MPDroid, an approach that combines static analysis and collaborative filtering to identify the minimum permissions for an Android app based on its app description and API usage. Given an app, MPDroid first employs collaborative filtering to identify the initial minimum permissions for the app. Then, through static analysis, the final minimum permissions that an app really needs are identified. Finally, it evaluates the overprivilege risk by inspecting the apps extra privileges, i.e., the unnecessary permissions requested by the app. Experiments are conducted on 16,343 popular apps collected from Google Play. The results show that MPDroid outperforms the stateoftheart approach significantly.

Demystifying Application Performance Management Libraries for Android Since the performance issues of apps can influence usersu0027 experience, developers leverage application performance management (APM) tools to locate the potential performance bottleneck of their apps. Unfortunately, most developers do not understand how APMs monitor their apps during the runtime and whether these APMs have any limitations. In this paper, we demystify APMs by inspecting 25 widelyused APMs that target on Android apps. We first report how these APMs implement 8 key functions as well as their limitations. Then, we conduct a largescale empirical study on 500,000 Android apps from Google Play to explore the usage of APMs. This study has some interesting observations about existing APMs for Android, including 1) some APMs still use deprecated permissions and approaches so that they may not always work properly; 2) some app developers use APMs to collect usersu0027 privacy information.