Information transfer techniques for mobile devices by "toss" and "swing" actions

In recent years, mobile devices have rapidly penetrated into our daily lives. Several drawbacks of mobile devices have been mentioned so far, such as their limited computational capability, small screen real estate, and, so on, as compared with notebook or desktop computers. However, by fully utilizing the most notable feature of mobile devices, that is, mobility, we can explore possibilities for a new user interface of the devices. In this paper, we use PDAs and propose intuitive information transfer techniques for them, which could not be achieved with notebook or desktop computers. By using the system called Toss-It, a user can send information from the user's PDA to other electronic devices with a "toss" or "swing" action, as the user would toss a ball or deals cards to others. We have developed a circuit board designed to be attached to a PDA and algorithms for recognizing "toss" and "swing" actions. Preliminary user studies of Toss-It indicated that it could correctly identify receivers of information by "toss" or "swing" actions. Our research project is in progress, and this paper describes the current status of the project by focusing on issues related to HCI (human computer interaction). We discuss about several critical issues to be investigated in our future studies.