What is a promising candidate for the next generation of interface technology

To compare the advantages and disadvantages of a "Graspable User Interface" a field study was carried out. During five days of the largest computer fair in Switzerland four different computer stations with (1) a command language, (2) a mouse, (3) a touch screen, and (4) a DigitalDesk interface was presented for public use. In this version of the DigitalDesk the user has to play a board game by moving a real chip on a virtual playing field against a virtual player. The task was to win the computer game "Go-bang". The reactions of the virtual player were simulated by "emoticons" as colored comic strip pictures with a corresponding sound pattern. We investigated the effects of these four different interaction techniques with two different methods: (a) an inquiry with a questionnaire, and (b) a field test for public and anonymous use. (a) Results of the inquiry: 304 visitors rated the usability of all four stations on a bipolar scale. The touch screen station was rated as the easiest to use interaction technique, followed by the mouse and DigitalDesk interface; the "tail-light" was the command language interface. One very important result was a significant correlation between "age" and "DigitalDesk usability". This correlation means that older people prefer significantly more a graspable user interface in form of the DigitalDesk than younger people. (b) Results of the field test: The analysis of 9'006 automatically recorded contacts to one of the four stations shows that the highest chance to win the game could be observed for the DigitalDesk interface technique. We conclude that the DigitalDesk as a graspable user interface with emotional, non-verbal feedback is a promising candidate for the next generation of dialog techniques.