Handbook of Research on User Interface Design and Evaluation for Mobile Technology Volume I Joanna Lumsden National Research Council of Canada Institute for Information Technology – e-Business, Canada INFORMATION SCIENCE REFERENCE Hershey • New York Acquisitions Editor: Kristin Klinger Development Editor: Kristin Roth Senior Managing Editor: Jennifer Neidig Managing Editor: Sara Reed Copy Editor: Joy Langel, Katie Smalley, and Angela Thor Typesetter: Jeff Ash Cover Design: Lisa Tosheff Printed at: Yurchak Printing Inc. Published in the United States of America by Information Science Reference (an imprint of IGI Global) 701 E. Chocolate Avenue, Suite 200 Hershey PA 17033 Tel: 717-533-8845 Fax: 717-533-8661 E-mail: [email protected] Web site: http://www.igi-global.com and in the United Kingdom by Information Science Reference (an imprint of IGI Global) 3 Henrietta Street Covent Garden London WC2E 8LU Tel: 44 20 7240 0856 Fax: 44 20 7379 0609 Web site: http://www.eurospanonline.com Copyright © 2008 by IGI Global. All rights reserved. No part of this publication may be reproduced, stored or distributed in any form or by any means, electronic or mechanical, including photocopying, without written permission from the publisher. Product or company names used in this set are for identification purposes only. Inclusion of the names of the products or companies does not indicate a claim of ownership by IGI Global of the trademark or registered trademark. Library of Congress Cataloging-in-Publication Data Handbook of research on user interface design and evaluation for mobile technology / Joanna Lumsden, editor. p. cm. Summary: "This book provides students, researchers, educators, and practitioners with a compendium of research on the key issues surrounding the design and evaluation of mobile user interfaces, such as the physical environment and social context in which a device is being used and the impact of multitasking behavior typically exhibited by mobile-device users"--Provided by publisher. Includes bibliographical references and index. ISBN 978-1-59904-871-0 (hardcover) -- ISBN 978-1-59904-872-7 (ebook) 1. Mobile computing--Handbooks, manuals, etc. 2. Human-computer interaction--Handbooks, manuals, etc. 3. User interfaces (Computer systems)--Handbooks, manuals, etc. I. Lumsden, Joanna. QA76.59.H36 2008 004.165--dc22 2007024493 British Cataloguing in Publication Data A Cataloguing in Publication record for this book is available from the British Library. All work contributed to this book set is original material. The views expressed in this book are those of the authors, but not necessarily of the publisher. If a library purchased a print copy of this publication, please go to http://www.igi-global.com/reference/assets/IGR-eAccess-agreement. pdf for information on activating the library's complimentary electronic access to this publication. 0 Chapter XXI Tools for Rapidly Prototyping Mobile Interactions Yang Li University of Washington, USA Scott Klemmer Stanford University, USA James A. Landay University of Washington & Intel Research Seattle, USA ABSTRACT We introduce informal prototyping tools as an important way to speed up the early-stage design of mobile interactions, by lowering the barrier to entry for designers and by reducing the cost of testing. We use two tools, SUEDE and Topiary, as proofs of concept for informal prototyping tools of mobile interac- tions. These tools address the early stage design of two important forms of mobile interactions: speech- based and location-enhanced interactions. In particular, we highlight storyboarding and Wizard of Oz (WOz) testing, two commonly used techniques, and discuss how they can be applied to address different domains. We also illustrate using a case study: the iterative design of a location-enhanced application called Place Finder using Topiary. In this chapter we hope to give the reader a sense of what should be considered as well as possible solutions for informal prototyping tools for mobile interactions. INTRODUCTION implementing an application (Gould et al., 1985). Informal prototyping tools can speed up an early- The iterative process of prototyping and testing stage, iterative design process (Bailey et al., 2001; has become an efficient way for successful user Klemmer et al., 2000; Landay et al., 2001; Li et al., interface design. It is especially crucial to explore 2004; Lin et al., 2000). These tools are aimed at a design space in the early design stages before lowering the barrier to entry for interaction design- Copyright © 2008, IGI Global, distributing in print or electronic forms without written permission of IGI Global is prohibited. Tools for Rapidly Prototyping Mobile Interactions ers who do not have technical backgrounds, and traditional desktop computing. One especially automatically generating early-stage prototypes promising form of context-aware computing that that can be tested with end users. The informal look has begun to see commercialization is location- and feel of these tools and their fluid input tech- enhanced computing, applications that leverage niques, for example using pen sketching (Landay et one’s current location as well as the location of al., 2001), encourage both designers and end users other people, places, and things (Li et al., 2004). to focus on high level interaction ideas rather than For example, mobile phone services allow users on design or implementation details (e.g., visual to locate friends and family (LOC-AID), provide layouts or colors). These details are often better real-time navigation (InfoGation) and monitor and addressed at a later stage. In this chapter, we focus motivate users toward their fitness goals by using on informal tool support for the early stage design phone-based GPS to measure the user’s speed, of interactive mobile technologies. In particular, distance and elevation (BonesInMotion). E911 we describe informal prototyping tools that we transmits a mobile phone user’s current location developed for two increasingly important forms when making emergency calls. However, location- of mobile interaction: speech-based interactions enhanced applications are hard to prototype and (Klemmer et al., 2000) and location-enhanced evaluate. They employ sophisticated technologies interactions (Li et al., 2004). such as location tracking and their target environ- The first of these two types of interactions, ment is mobile and in the field. Topiary (Li et al., speech-based, works well on mobile phones, 2004) demonstrates how high-level tool support the major platform of mobile computing. These can be provided for lowering the threshold and cost devices often have tiny screens and buttons to for designers to design and test location-enhanced increase mobility, which makes speech interaction applications. an important alternative. Although the accuracy Using SUEDE and Topiary as proofs of concept, of speech recognition is an important concern we highlight two techniques commonly used in for a successful speech-based UI, the real bottle- informal prototyping tools: storyboarding and neck in speech interface design is the lack of Wizard of Oz (WOz) testing. To overcome the basic knowledge about user “performance during technical barrier for design, both SUEDE and computer-based spoken interaction” (Cohen et Topiary employ a storyboarding-based approach al., 1995). Many interaction designers who could for specifying interaction logic. To allow easy contribute to this body of knowledge are excluded testing of prototypes, both tools employ WOz from speech design by the complexities of the core approaches where a human wizard simulates a technologies, the formal representations used for sophisticated, nonexistent part of the prototype specifying these technologies, and the lack of ap- such as location tracking or speech recognition. propriate design tools to support iterative design To demonstrate how these types of tool can actu- (Klemmer et al., 2000). SUEDE (Klemmer et ally help prototype and test mobile technology, we al., 2000) demonstrates how tool support can be introduce a case study using Topiary to design the used in the early stage design of speech-based Place Finder application. user interfaces. The second of these two types of interactions, location-enhanced, is important because of its BACKGROUND implicit nature. While the explicit input channels (e.g., keyboarding or mouse pointing) available User interface tools have been a central topic in on mobile technology are more limited than on HCI research. An extensive review of user interface the desktop, the bandwidth of implicit input (us- tools can be found in (Myers et al., 2001). A large ing contextual information) is greatly expanded number of research prototypes and commercial on mobile platforms. Mobile technology is more products have been developed for rapid prototyp- available in our context-rich, everyday lives than ing of user interfaces (Apple, 1987; Bailey et al., Tools for Rapidly Prototyping Mobile Interactions 2001; Hartmann et al., 2006; Klemmer et al., 2000; all of the application logic by manipulating the in- Landay et al., 2001; Li et al., 2004; Lin et al., 2000; terface in response to user input. This significantly Macromedia; MacIntyre et al., 2004). reduces the time and labor required to create a In particular, informal prototyping tools are testable prototype. As both speech-based inter- aimed at the early stages of a design process, and are faces and location-enhanced computing involve used to create early-stage prototypes for testing