ABSTRACT
9.1 Understanding 3D Touch
Notwithstanding the initial excitement around multi-touch interfaces it has quickly become apparent that using touch as the primary input modality poses (even in 2D contexts) some fundamental limitations for traditional interface design [Benko and Wigdor 10, Müller-Tomfelde et al. 10]. Some of the most important problems are the missing hover, occlusion and precision problems and – depending on the implementation – missing or non-adequate visual feedback. In particular, the size of the human fingers and the lack of sensing precision make precise touch screen interactions difficult [Benko et al. 06, Holz and Baudisch 10]. The approaches to handle this can be roughly separated into two groups. Approaches from the first group try to shift the problem into the interface design space. Therefore, precise selection is distinguished as a new interface requirement, which demands additional functionality and thus an extended set of interaction metaphors or techniques.
