Looking at mobile solutions or wearable computing, it immediately becomes apparent that their user interfaces call for di?erent solutions than the desktop paradigm. This is not only due to the very small size of the displays but also predominantly to the need for a much stronger dependency on the applications. In addition, they feature a use of environmental sensors which has never been seen before enabling applications to run in an Ambient Intelligence Environment. This development requires new solutions and constitutes new research questions. With this book, Dr. Witt contributes to the goal...