Hand-specific on-skin (HSoS) gestures are a trending interaction modality yet there is a gap in the field regarding users' preferences about these gestures. Thus, we conducted a user-elicitation study collecting 957 gestures from 19 participants for 26 commands. Results indicate that (1) users use one hand as a reference object, (2) load different meanings to different parts of the hand, (3) give importance to hand-properties rather than the skin properties and (4) hands can turn into self-interfaces. Moreover, according to users' subjective evaluations, (5) exclusive gestures are less tiring than the intuitive ones. We present users' subjective evaluations regarding these and present a 33-element taxonomy to categorize them. Furthermore, we present two user-defined gesture sets; the intuitive set including users' first choices and natural-feeling gestures, and the exclusive set which includes more creative gestures indigenous to this modality. Our findings can inspire and guide designers and developers of HSoS.

We observe an increasing interest on usage of full-body interaction in games. However, human-to-human social touch interaction has not been implemented as a sophisticated gaming apparatus. To address this, we designed the Sensation, a device for detecting touch patterns between players, and introduce the game, Shape Destroy, which is a collaborative game designed to be played with social touch. To understand if usage of social touch has a meaningful contribution to the overall player experience in collaborative games we conducted a user study with 30 participants. Participants played the same game using i) the Sensation and ii) a gamepad, and completed a set of questionnaires aimed at measuring the immersion levels. As a result, the collected data and our observations indicated an increase in general, shared, ludic and affective involvement with significant differences. Thus, human-to-human touch can be considered a promising control method for collaborative physical games.