The demands on today’s learner have changed over the recent years as the understanding of his role evolved. Getting away from the traditional top-down approaches, the learner is more and more in control of selecting learning resources or choosing the right learning techniques. On the one hand, by following the idea of a learner-centric Personal Learning Environment it is now possible to freely design an own learning environment with all required tools to improve the learning process. On the other hand, the ubiquitous usage of mobile devices such as smart phones or tablet computers creates the basis for new modern learning scenarios. While different applications for the devices already allow an individual aggregation of tools they are still highly separated and cannot interact beyond the borders of one application. In this paper, we present a new approach realizing application ecologies on mobile devices which allow integrating services and functionalities of one application into another one. This may happen ad-hoc without involvement of application developers resulting in high extensibility. Furthermore, it allows the user to adjust the app system according to his needs and creates the impression of one seamless mobile PLE consisting of an adjustable set of applications.