The convergence of the Internet and telecommunication sector is finally happening. Currently end users expect entertainment applications and services to be available on their mobile phone. This applies especially to games, videos, and music sold via so-called value added data services. They are used nowadays to increase revenue in addition to the voice services and made a major change to the whole telecommunication market. That is why one may find more complex business models as a result of an increased number of key players, in comparison to the established voice services. The author...