69 Pages, 27 Figures, 5 Tables, 62 References, 10 Appendices\nFramed against the OPTIMOS project, this thesis analyses the requirements of mobil-ity applications based on the principles of user-centered-design. The technology of Near-Field-Communication (NFC) enables a significant improvement of smartphone-based e-ticketing in public transportation. Therefore, the requirements of customers will be explored through an empirical observation. The research methodology is de-rived through a study of related research.\nWorkshops were designed, implemented and then evaluated in order to identify user requirements in terms of mobility applications. The workshop responded to heteroge-neous needs in public transportation, and therefore examined different application sce-narios for archetypical user groups. The requirements of these specified use-cases are determined by test persons within two workshops conducted in Dusseldorf and Berlin. The findings are divided into three subcategories. First, test persons expect a high validity of information. Second, workshop participants demand an intuitive design of the user interface. A third key element is the personal adjustment of the application according to individual preferences.