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In our first prototype, we presented the users with left and right arrows to choose “A-M” or “N-Z” (Fig. 1).
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Figure 1. Navigating in an early prototype
Paper prototyping suggested that after learning how to use our keyboard, users would quickly be able to decide whether to initially go left or right. However, as we implemented this and tried using it ourselves, we realized that many users might never become efficient at this. Heuristic evaluations and user testing confirmed our suspicion. We improved this by displaying all characters up front so that rather than forcing the user to figure out which half of the alphabet contains his target letter, he can simply locate his letter visually (Fig 2.)Wiki Markup \[Screenshot\]
Figure 2. Navigating in the final design
After navigating left or right, our early prototype opened up a new set of choices that required the user to navigate left or right again (Fig 3.)
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The results of the timing data is summarized in Figure 8. We see that typing these phrases with our keyboard takes roughly twice as long as it does with the stock keyboard. Additionally, the average time to edit “Call me maybe” to “Call me baby” with the control keyboard was 5.5s; the average time to edit with the experimental keyboard was 12.8s. Our observations during user testing suggest that the reason for this is that our participants were heavy gamers so they were very familiar with the control keyboard. Since they did not have as much experience with the experimental keyboard, they lacked muscle memory in navigating to letters. In the future, we would like the resources to do a more fair evaluation in which test participants have not had any experience with game controllers.
Figure 8. Average time to type each phrase for the Wii keyboard (control) and our keyboard (experimental).
After completing the assigned tasks, we asked each user which keyboard they preferred. Four of the six participants said they preferred the experimental keyboard - they believed that with a little more use they would become efficient enough with it that it would be faster than using the control keyboard.
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