The subject of applications of MDE is vast and rapidly evolving. Usually one may consider three important areas: generation of software artifacts, discovery of models from structured systems and interoperability between heterogeneous systems. As the third part of this series of tutorial, this article will show these three areas of increasing complexity are constantly evolving. Another classification of MDE applications may consider various domains like health care, military operations, automotive engineering, aeronautics, embedded systems, information systems, Web engineering, etc. We will instead take a typological approach and show how the typology of applications may be related to a classification of models and metamodels.