A robust and efficient birthmark-based android application filtering system

Since it is very easy to decompile and repackage Android applications (or apps), many paid apps in the official Android Market are exposed to software piracy such as illegal copy, license cracking, and illegal distribution. To address this problem, we can employ app filtering systems that can prevent OSP servers from distributing illegally copied or tampered apps. In this paper, we propose a birthmark-based Android app filtering system. The system extracts birthmarks from APK files, and compares the birthmarks to examine if a given APK file is actually identical to one of (paid) original apps, that is, the APK file is a duplicated or tampered one. The experimental results show that the system is efficient and robust in the sense that the birthmark size is very small and the tampered apps can be identified effectively.