In this chapter, recent research on context-aware mobile and wearable computing is described. Starting from the observation of recent developments on Smartphones and research done in wearable computing, the focus is on possibilities to unobtrusively support the use of mobile and wearable devices. There is the observation that size and form matters when dealing with these devices; multimodality concerning input and output is important and context information can be used to satisfy the requirement of unobtrusiveness. Here, Frameworks as middleware are a means to an end. Starting with an introduction on wearable computing, recent developments of Frameworks for context-aware user interface design are presented, motivating the need for future research on knowledge-based intuitive interaction design.