Mobile Phones and the Keystroke-Level Model

The Keystroke-Level Model gives the time it takes for an expert to do a task error-free. It does this by using operators that represent keystrokes, mouse movement and presses, the movement of hand between the two, and the the time spent mentally preparing for an operator. While these operators are clearly linked to the desktop, these operators can work on mobile phones as well. We present an open source tool, KLM-Qt, that can examine events that are delivered to an application and convert them into Keystroke-Level Model operators. This has the advantage that all that needs to be done is demonstrate the application to get a model, resulting in a savings of time. We include how the tool works along with the details of its implementation. To test the tool, we run it along with other desktop evaluation methods for a couple of mobile phones: the Trolltech Greenphone, the FTC Neo1973, and the Apple iPhone. We find that these evaluation methods show promise for mobile devices and should be pursued further when doing evaluations of applications on mobile phones.