CliSeAu for Android Applications: Design, Case Studies and Evaluation Dynamic enforcement is a mechanism to ensure compliance of programs or systems with a specified security policy. CliSeAu is a tool for dynamically enforcing runtime policies for Java programs in a decentralized and distributed fashion. This Master’s Thesis introduces CliSeAu for Android – an extension to CliSeAu that can be used to enforce decentralized and distributed runtime policies in Android applications. CliSeAu for Android provides a unique and novel enforcement approach for Android applications that has – to the best of our knowledge – not yet been examined in the literature. While Android is based on Java, it introduces some aspects that are platform specific and works with a different format for executable applications than plain Java does. The developed extension provides an accessible interface to Android’s peculiarities like the Application lifecycle and interprocess communication model. In realistic case studies, we show that CliSeAu for Android offers an efficient enforcement process.