INTERFACE AND INTERACTION DESIGN FOR ONE-HANDED MOBILE COMPUTING. Amy ...

282 Pages·2007·2.23 MB·English

by  Matthew Hill

ABSTRACT

Title of Document: INTERFACE AND INTERACTION DESIGN
FOR ONE-HANDED MOBILE COMPUTING.

Amy Kathleen Karlson, Ph.D., 2007

Directed By: Associate Professor Benjamin B. Bederson,
Department of Computer Science

Mobile phones are not only a ubiquitous social accessory, but rapid technology advances
have transformed them into feature-rich, Internet-enabled mobile PCs⎯a role once
reserved for touchscreen-based personal digital assistants (PDAs). Although the most
widespread phone styles in circulation feature the classic combination of numeric keypad
and non-touchscreen display, larger touchscreen devices are gaining ground, as indicated
by the fervor surrounding new devices such as Apple’s iPhone and LG’s Prada phone.
Yet as devices evolve, users will remain constrained by the limits of their own visual,
physical, and mental resources. My research has focused on the specific limitation that
mobile users often have only one hand available to operate a device, which can be
especially problematic for touchscreen-based devices, since they are frequently designed
for two-handed stylus operation. Considering the growing volumes of data that small
devices can now store and connect to, as well as the expanding cultural role of mobile
phones, improving usability in mobile computing has potentially enormous implications
for user productivity, satisfaction and even safety.
My own exploratory surveys have suggested that one-handed use of mobile
devices is very common but that today’s hardware and software designs do not support
users in performing many tasks with only one hand. Motivated by these findings, the
research goal of this dissertation is to contribute substantial knowledge in the form of
empirically backed design guidelines and interaction techniques for improving one-
handed usability and operation of mobile devices, with particular emphasis on those with
touch-sensitive displays. The guidelines for one-handed mobile device design are the
product of a series of studies conducted in pursuit of foundational knowledge in user
behavior, preference, thumb capabilities and touchscreen-thumb interaction
characteristics for single-handed device use. I also demonstrate the application of these
guidelines through the development and evaluation of four applications. Two involve
designs for navigating among programs, one provides an interface for searching large
data sets, and the last offers a generalized mechanism for controlling arbitrary
touchscreen interfaces with a thumb. Each of these applications explores a different one-
handed interaction technique and offers perspective on its viability for one-handed device
use.
INTERFACE AND INTERACTION DESIGN FOR ONE-HANDED MOBILE
COMPUTING.

By

Amy Kathleen Karlson

Dissertation submitted to the Faculty of the Graduate School of the
University of Maryland, College Park, in partial fulfillment
of the requirements for the degree of
Doctor of Philosophy
2007

Advisory Committee:
Associate Professor Benjamin B. Bederson, Chair
Assistant Professor François Guimbretière
Associate Professor José Contreras-Vidal
Professor Ashok Agrawala
Professor Adam Porter
© Copyright by
Amy Kathleen Karlson
2007
Dedication

To My Mother and Father
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Acknowledgements
I would like to extend my utmost thanks to my advisor, Dr. Ben Bederson, without whose
guidance, patience, frankness and encouragement this thesis would not have been
possible. I am also very grateful to my committee members, Dr. François Guimbretière,
Dr. Ashok Agrawala, Dr. Adam Porter, and Dr. José Contreras-Vidal, for donating their
time and expertise in making this document the best possible representation of my work.
I would also like to thank the entire staff and members of the HCIL Lab, who
have been a joy to work with over the years. In particular, Aaron Clamage, Anne Rose,
and Kiki Schneider were always friendly, responsive, and expert in their technical and
administrative support. A special thanks to Ben Shneiderman and Catherine Plaisant for
their leadership and Bongshin Lee, Adam Perer, Jerry Fails and Georg Apitz for their
friendship.
I would also like to thank Microsoft Research, which funded the entirety of this
thesis research, as well as their Visualization and Interaction Research (VIBE) group,
who hosted me for two exceptionally educational and resourceful summer internships.
George Robertson and Mary Czerwinski provided unparalleled support and guidance, and
together with Greg Smith, Bryan Meyers, Dan Robbins, and Desney Tan, made enormous
intellectual, technical, and social contributions to my summer research experience. In
association, Patrick Baudisch and Dan Vogel’s work on finger-based touchscreen
interaction has had substantial inspirational and motivational impact on my own research.
Finally, a host of family and friends have had unfailing faith in me over the years,
and to whom I am deeply indebted: David Karlson, Sarah Karlson, Patience Landry,
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Richard Landry, David Levin, Edward Manuel, James Pasmantier, Emily Porter, David
Richards, Kathleen Richards, Lisa Robey, Karen Salvini, Megan Spitz, Pamela Spitz,
Chris Stone, Catherine Thompson, Jacqueline Wahl, Kendra Walther, and Jordan
Wilkerson.
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Table of Contents
Dedication.. ........................................................................................................................ii
Acknowledgements............................................................................................................iii
Table of Contents.................................................................................................................v
List of Tables.....................................................................................................................xi
List of Figures...................................................................................................................xii
Chapter 1 Introduction.....................................................................................................1
1.1 The Rise of the Mobile Phone as Personal Computer..........................................1
1.2 Challenges in Mobile Computing.........................................................................3
1.3 One-Handed Use of Mobile Touchscreen Devices...............................................5
1.4 Research Strategy..................................................................................................7
1.5 Thesis Contributions...........................................................................................11
1.5.1 Foundations: Guidelines for One-Handed Mobile Device Interaction.......11
1.5.2 Applications: Interaction Techniques for One-Handed Data Access..........13
1.6 Thesis Organization............................................................................................14
Chapter 2 Foundations: Why Design for One-Handed Mobile Devices?.....................16
2.1 Related Work......................................................................................................16
2.1.1 Effects of Device Size on Design................................................................16
2.1.2 Attention and Mobility................................................................................18
2.1.3 Impact of Form on Physical Resource Demands........................................20
2.1.4 Strategies for Reducing Hand Requirements..............................................24
2.1.5 The Role of Audio in Mobile Interaction....................................................29
2.2 Exploratory Study 1: Field Study.......................................................................32
2.2.1 Method.........................................................................................................32
2.2.2 Measures......................................................................................................33
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2.2.3 Results.........................................................................................................33
2.2.4 Discussion...................................................................................................35
2.3 Exploratory Study 2:Web Survey.......................................................................36
2.3.1 Method.........................................................................................................36
2.3.2 Measures......................................................................................................37
2.3.3 Results.........................................................................................................38
2.3.4 Discussion...................................................................................................42
2.4 Conclusion..........................................................................................................43
Chapter 3 Foundations: Human Factors in One-Handed Mobile Device Interaction...45
3.1 Related Work......................................................................................................45
3.1.1 Ergonomics..................................................................................................45
3.1.2 Target Sizes for Touchscreens....................................................................48
3.1.3 Gestures for Input........................................................................................53
3.2 Thumb Movement Study....................................................................................56
3.2.1 Equipment...................................................................................................57
3.2.2 Participants..................................................................................................60
3.2.3 Tasks............................................................................................................60
3.2.4 Design..........................................................................................................61
3.2.5 Procedure.....................................................................................................61
3.2.6 Measures......................................................................................................64
3.2.7 Results.........................................................................................................66
3.2.8 Discussion...................................................................................................70
3.3 Target Size Study................................................................................................72
3.3.1 Procedure.....................................................................................................74
3.3.2 Participants..................................................................................................74
3.3.3 Equipment...................................................................................................75
3.3.4 Discrete Target Phase..................................................................................75
3.3.5 Serial Target Phase......................................................................................79
3.3.6 Discrete Target Phase Results.....................................................................81
3.3.7 Serial Target Phase Results.........................................................................86
3.3.8 Discussion...................................................................................................89
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3.4 Gesture Study......................................................................................................91
3.4.1 Gesture Language........................................................................................92
3.4.2 Tasks............................................................................................................93
3.4.3 Materials......................................................................................................94
3.4.4 Participants..................................................................................................95
3.4.5 Measures......................................................................................................95
3.4.6 Procedure.....................................................................................................96
3.4.7 Results.........................................................................................................97
3.4.8 Discussion...................................................................................................98
3.5 Conclusion........................................................................................................100
Chapter 4 Applications: Touchscreen Design Strategies for One-Handed Mobile
Computing..................................................................................................102
4.1 Overview...........................................................................................................103
4.2 A Comparative Design Strategy.......................................................................104
4.3 Related Work....................................................................................................106
4.4 AppLens............................................................................................................108
4.4.1 AppLens Zoom Levels..............................................................................109
4.4.2 Gesture-Based Cursor Navigation.............................................................110
4.4.3 Command Gestures...................................................................................111
4.4.4 Using Command Gestures within AppLens..............................................113
4.5 LaunchTile........................................................................................................113
4.5.1 Zone View.................................................................................................115
4.5.2 Panning Techniques..................................................................................115
4.5.3 Zooming Out to the World View..............................................................116
4.5.4 Zooming In to an Application...................................................................117
4.5.5 Zoom Control............................................................................................117
4.5.6 Application-Level Interaction...................................................................118
4.6 Implementation.................................................................................................119
4.7 AppLens and LaunchTile Formative Study......................................................120
4.7.1 Participants................................................................................................120
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