Applications for street navigation are widely used and leverage the massive publicly available map data sources. On the other hand, applications for pedestrian navigation, especially navigation within buildings, are few and far between. This paper describes the development of a native Android app for pedestrian navigation, including the preparation and representation of navigation data in the form of a graph, design of the graphical user interface, and selected implementation details. Based on floor plan images and building on the graph data generation tool developed in the course of a previous research project, the navigation data for buildings in the Vaihingen campus of the University of Stuttgart were modelled as an abstract graph. The application allows the user to specify the start and goal points, and finds an optimal route between them. The performance and scalability potential of the app was assessed in a benchmarking process.