3dcityThis thesis covers the development of a network supported multiuser augmented reality application for mobile devices. A presenter can load 3D models dynamically, display them on an augmented reality 2D tracker and is capable of manipulating certain single objects. These manipulations are already well-defined in advance through the hierarchy of the 3D object. Executable manipulations are translation, rotation, scaling and the change of materials. Any number of spectators can follow the presentation with their own device from a point of view of individual choice. If the data of the model is not present, Thoughts are made in advance, as follows, as well as chosen solutions. With the prototype of a user study. The choice is between static, dynamic and combined lighting. Additionally, the app is evaluated in the study. Read More