The recent rise of smartphones has triggered a revolution in mobile development. As a result of this incremental mobile innovation, new software engineering techniques, software documentation, and tools adapted to the mobile platform remain essential in order to help developers to better understand, analyze, and bootstrap porting mobile applications. In this paper, the authors propose a model-driven reverse-engineering approach based on static analysis, which describes a semantic metamodel of the iOS mobile application and extract design information (such as user interfaces, activity diagram, entities, framework and library dependencies) in order to generate the functional specification documentation and the Android UI skeleton. Thus, aiding the project team, who has in charge porting the app to another mobile platform, to agree upon a consensus on what has to be implemented and safe development cost by auto generating the Android UI skeleton project. To experiment this approach, the authors have implemented a tool called iSpecSnapshot. Moreover, they evaluate the performance of iSpecSnapshot by an experiment involving iOS applications that are ported to Android platform.