Clear Panels: A Technique to Design Mobile Application Interactivity Quincy Brown, Elizabeth Bonsignore, Leshell Hatley, Allison Druin, Gregory Walsh, Elizabeth Foss, Robin Brewer, Joseph Hammer, Evan Golub Human Computer Interaction Lab University of Maryland, College Park 2117A Hornbake Building, South Wing College Park, Maryland 20742 qbrown@umd.edu, allisond@umiacs.umd.edu ABSTRACT We introduce a design technique, Clear Panels, to design interactive mobile device applications. Using mixed- fidelity prototyping, a combination of low- and high-tech materials, participants refine multiple aspects of a mobile application’s design. Clear Panels supports writing and sketching via a transparent overlay affixed atop a mobile device screen. It enables design partners to refine their gesture-based interactions on actual devices. The technique has been successfully implemented in the design of children’s mobile applications. The technique leverages and extends longstanding interaction design methods to include mobile and hand-held technologies. Importantly, we show it is effective in raising participants’ awareness of key mobile application design issues without constraining their creativity. ACM Classification Keywords H.5.2 [User Interfaces] Prototyping, Input devices and strategies INTRODUCTION The ubiquity of mobile devices in today’s society coupled with the growing number of children who are digital natives [1] underscores the need for design methods to address the creation of mobile device applications for young children. Participatory design approaches have been used for decades to design desktop applications that rely on traditional interaction technologies such as mouse or keyboard input, and large displays [8, 10]. However, existing methods and techniques transfer inadequately to the design of mobile applications due to constraints, such as small sizes, and affordances, such as portability and location awareness [4, 10, 14]. Further, as mobile technologies shift from stylus and graffiti-based inputs towards touch and gesture-based inputs, new interaction modes must be incorporated into mobile applications. Figure 1 Using the Clear Panels design technique with children Participatory design methods involving children (aged 4- 12) have been used worldwide to design novel technologies [2, 3]. However, child design partners, who may be digital natives but not expert mobile device users, can benefit from new methods that support children’s understanding of affordances and constraints associated with the mobile environment. The Clear Panels technique has its roots in mixed-fidelity prototyping [7, 12]. The technique employs a combination of high-tech mobile application prototypes and a clear panel for low-tech sketching (Figure 1), and focuses on incorporating attributes specific to mobile devices into the participatory design process. The use of the low-tech clear plastic panel affixed to the high-tech mobile device prototype enables designers to authentically maintain the affordances, such as mobility, of the mobile device and remain in context with the actual device in a way that an inauthentic replica, such as a wooden block, would not. We have found that Clear Panels aids design partners, specifically children, in refining the design of several facets of mobile device applications. We employ actual devices rather than mock-ups or low-tech prototypes, to enable design partners of all ages to experience the actual weight, screen size, and interaction of a mobile device rather than use a simulated or artificial interaction. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. DIS 2010, August 16-20, 2010, Aarhus Denmark Copyright � 2010 ACM ISBN 978-1-4503-0103-9, 2010/08 - $10.00. 360