because it is “a simple action that can be performed
by most people” and it “has an element of fun and
delight to it.” While one can’t expect the author to
prescribe these particular associations and anticipate all potential contextual nuances, identifying at
least some of these associations could provide very
helpful information for the designer who wishes
to use these gestures in a meaningful, appropriate way. “Rotate to change state” for example, can
be enriched by referring to our daily experience
with faucets and other knobs that we encounter
throughout daily life. (In the book’s introduction,
the author brings up some interesting insights into
the prevalence of gestural interfaces in public rest-rooms, yet he neglects to refer back to these very
real objects when discussing how to actually apply
these gestures to new interactive systems.) Surely
these references will lose importance over time
as objects we once knew disappear from contemporary everyday life. Nonetheless, the emotional
meaning that physical objects evoke cannot be
ignored when discussing any kind of gesture, and
selecting the right gesture for a given context is a
fundamental part of the design process.
While it is understandable that a book with a
focus on touchscreens and interactive devices
(and one that is published by O’Reilly, creator of so
many software “bibles”) would necessarily be somewhat technical in its approach, it feels awkward to
read about such a human subject as though it is a
catalog of parts. It is odd, for example, to thumb
through the appendix of actual human gestures
presented in the format of a lengthy user manual
for a new device. Though looking at these gestures
in isolation is an interesting exercise, having such
a detailed guide to something we all experience
firsthand (the movement of our own bodies) is of
questionable value. Since we already know these
gestures innately, what requires reflection is how
to apply them to an interaction design problem. It
is not particularly interesting to read a description
of “punch” as “A fist is pushed straight out in the
air” or “hand gun” as “The hand is formed into the
shape of a pistol, with the extended forefinger as
the barrel and the thumb cocked upwards,” with
possible uses being “selection, activation,” while
being all too aware of what these gestures really
imply to a human being either making them or
witnessing them being performed. Even something
as seemingly mundane as “finger drum” has the
potential for a richer communicative semantic
beyond “tapping out a rhythm.” The list of gestures
is exhaustive and the photos are illustrative, but
perhaps such quantity is unnecessary. It would be
great to see more of a discussion of the significance
of these gestures within the context of an interface
narrative, even if only as a case study. For example,
“Thumbing nose” states, “An offensive gesture,
albeit a playful one”; it’s a description that begins to
imply how the gestures offer social cues, but for the
most part, the world sketched out in Saffer’s book
is one in which a smile does little beyond triggering
some specified system behavior.
Again, it is understandable that the focus of the
book is to help designers determine specific ways
to trigger software events from hardware-based
inputs. It cannot be all things to all people, and the
author does a good job of pointing the reader to
resources for further investigation into other topics
such as sign language, choreography, and body-lan-guage taboos. Still, it would be helpful to learn of
at least one example where the social and cultural
significance of the gestures was discussed in a way
that could then allow the reader to get a glimpse
into a process that considered these factors.
In Saffer’s preface he refers to this book as a
“starting place and a reference point,” and ultimately, that is the best description for its role in
any interaction designer’s collection of reading
materials. It will be a great primer for students and
a good introduction for others who are new to the
field and need to quickly ramp up their knowledge
of electronically enhanced, gesturally based interfaces. However for those who are familiar with the
O’Reilly “animal series,” Designing Gestural Interfaces
may come up short when compared to some other
titles. For seasoned interaction and industrial
designers, it can serve as a visual dictionary of
sorts and will be helpful at the brainstorming
stage, but may not be so useful when moving past
that phase to the more critical parts of the design
decision-making process.
ABOUT THE AUTHOR Carla Diana is an indus-
trial and interaction designer with a diverse back-
ground in design, technology, and product
research. Currently a senior interaction designer at
Smart Design in New York, she is working on a vari-
ety of projects from floor-cleaning appliances to
emotive robots. For more information, visit www.carladiana.com.
January + February 2009
DOI: 10.1145/1456202.1456214
© 2009 ACM 1072-5220/09/0100 $5.00