Towards Platform Independence of Mobile Applications: Metamorphosing Android Applications for the Web

In the last years the number of platforms has increased dramatically - especially in the mobile sector. Developing a native mobile application for each platform is costly. There are common approaches to develop within one code base for many platforms. So-called cross-platform-tools can help developers to decrease the effort of making platform specific versions. However, most of these tools are dealing with JavaScript and therefore an existing native application, which is written in Java, C# or Objective-C can hardly be reused. This paper shows an automated conversion of platform specific Android applications to platform independent Web applications by using the Google Web Toolkit (GWT). This converter provides code reusability of existing Android applications and platform independence. The converter uses the Eclipse Java Development Tools (JDT) for processing the source code. On the one hand, Android wrapper classes provide the API calls, which access internally GWT code or directly HTML5 features. On the other hand, source code, which does not fulfill the GWT's requirements, is converted. A case study confirms that this converter can be easily applied to a range of Android applications for converting them to platform independent Web applications.