Paper Reading #28: Experimental Analysis of Touch-Screen Gesture Designs in Mobile Environments

Andrew Bragdon is a PhD computer science student at Brown University.
Eugene Nelson also represents Brown University.
Yang Li is a senior researcher at Google Research.
Ken Hinckley is a principal researcher at Microsoft Research.

This paper was presented at CHI 2011.

Summary


Hypothesis
The researchers presented the hypothesis that there are certain ways to control mobile devices through gesture techniques and soft buttons that allow for easier interaction in different ways.

Methods
Researchers tested various different types of input methods to control the phone.

First, they looked at hard button initiated gestures. This means that a physical button mounted on the hardware would signal when a gesture could be drawn on the screen. So the user would have to first push the hard button before they could start the gesture.

Bezel gestures happen when the user starts the gesture off the screen and bring their finger over to the main touch area. This allows the phone to know when to start allowing gesture input.

To allow for a "performance baseline", the researchers also used soft buttons for testing purposes.

They also defined several different types of gestures: paths versus marks.

For testing which gesture types worked better in different environments, they looked at the accuracy and time of the gesture during various motor activity (sitting and walking) and distraction level (no distraction, moderate situational awareness, attention-saturating task).

15 participants completed this study.

Results
Researchers found that soft buttons and gestures worked about the same when the user was looking at the phone. However, when the user wasn't looking at the phone, bezel gestures were the easiest and most accurate.

When distracted, bezel gestures again performed better than soft buttons. Researchers stated that this was encouraging because it means that gestures can actually improve performance.

Discussion

As I mentioned last week, these kinds of studies are important. These kinds of tests ensure that gesture space (or a given input method) is actually truly better than what is currently used by the mainstream groups. Not only does this research prove that gestures can perform better than soft buttons, but it also helped show which gestures would work better.