At large construction sites many people often work on different services at the same time. To make this huge planning and coordination effort easier, the Sablono Onsite software enables the user to collectively and in real time document the progress of a construction site on a central platform. In frames of the research project Usetree and a cross university partnership with the TUB (Human Factors) and UDK (Interactive Systems), the app was tested in its Usability of the Software, to generate requirements and new designs.