Mobile DRM--usability out the door?

One current trend is that content such as e-books, music, videos and now also games and applications are increasingly being distributed across the Internet, and more and more of it is protected by a Digital Rights Management system. Another trend is that this content is consumed using an increasing number and variety of devices, some of which are mobile. The characteristics of mobile terminals mean that the user experience of consuming protected content is rather different from the experience of using a desktop computer. Mobile human-computer interaction research addresses many of the usability issues with mobile terminals. This study tries to extend these theories by answering the question if, and what, usability issues arise with the different Digital Rights Management implementations for mobile terminals. Therefore, this paper gives an overview of the different mobile DRM implementations and discusses the specific and general usability problems of each implementation.