Smart Phone Keyboard Layout Usability

Introduction

The QWERTY keyboard layout has existed since Ulysses S. Grant was President of the United States, with only a few minor changes occurring to that keyboard layout over the years. But when this keyboard transitioned to smart phones, users changed the primary hand digits used to type from ten fingers to (usually) only one or two thumbs. Today’s smart phones predominantly use soft keyboards with touch screens, which means many costs identified in past research related to keyboard hardware are eliminated.

The keyboard itself is the longest-lasting component for computers that has undergone the least amount of change compared to other components such as visual displays, secondary storage, data/connection ports, printers, and processors. One may wonder whether any improvement is possible, regardless of whether that change is likely to be adopted by users. History has shown several attempts at introducing alternative keyboard layouts with the more famous and well-known example being that of the Dvorak layout (Dvorak, 1943; Dvorak, Merrick, Dealey, & Ford, 1936). And while some studies have demonstrated the benefits of using an alternative layout (Buzing, 2003; Kinkead, 1975; Lewis, Kennedy, & LaLomia, 1999; MacKenzie, Zhang, & Soukoreff, 1999), the adoption of those alternative layouts did not occur and QWERTY continues to be the keyboard layout of choice.

When mobile phones first arrived in the general consumer market at the end of the 20th century, the keyboard interface mimicked the 12-key, touch-tone phone layout as seen in Figure 1. This layout made logical sense at that time. Especially on early mobile analog phones, the primary phone’s usage was simply to make phone calls. And the 12-key layout matched closely the mental model held by people at that time, not to mention space for buttons was at a premium. When SMS (Short Message Service) messaging, commonly known as texting today, began growing in popularity, the 12-key layout proved to be inefficient and cumbersome for users. Therefore, a full-sized keyboard was needed, and the QWERTY keyboard was selected because of its familiarity to most users.

When people use a hand-held mobile device to send text messages, however, they do not interact with the keyboard in the same way as they would on a desktop or laptop computer. Instead of using ten fingers, users normally type with only one or two thumbs. Some individuals may even use one index finger to type the individual characters (Oulasvirta et al., 2013). Therefore, the purpose of this study is to determine if users would be more productive with and more likely to adopt a gradually changing keyboard layout (for example, swapping two keys at a time such as the letters ‘F’ and ‘E’) as compared to an immediate complete remapping of the keyboard layout. Foundationally, this deals with the adaptation factor for human beings