In this paper, we present an updated set of experimental tasks and measures for large multi-touch (MT) input devices. In addition to a multi-user condition, we have employed an updated set of tasks, as well as subjective measures for user enjoyment. In the first experiment (a target acquisition task with two moving targets), the MT was more efficient than the mouse. Surprisingly, we found that the reduced accuracy of MT did not affect the perceived usability, or the enjoyment of the users. In the second experiment (a multiple shapes docking task), the MT was again more efficient and enjoying than the mouse. In the two-user condition, we found that performance and enjoyment was always higher than the single-user conditions, regardless of input device and task. Besides the quantitative results, we observed that users employed diverse interaction strategies in the MT condition, such as bi-manual input. The proposed tasks and the results support the use of MT in entertainment applications (multimedia and video-games), collaborative work, and scientific visualizations with complex data.
