Article: Gestural Interfaces: A Step Backward in Usability D. Norman, J. Nielsen
In this article Don Norman claims that developers responsible for gestural interface design are ignoring interactive design principles, thus creating an unnecessary usability crisis. (Norman & Nielsen, 2010). The reasons for these misguided oversights appear related to ignorance, a desire for companies to quickly release creative initiatives and hence justify inadequate laboratory testing. Companies are also trying to protect their proprietary products through adherence to ill-informed company design guidelines rather than utilizing more broadly recognised design principles.
Norman indicates that users of gestural interfaced devices are frustrated, confused and on occasions unexpectedly surprised. Using fundamental, non-technical, tested principles of design, Norman outlines specific issues with Android devices and iPhones. Problems related to visibility, feedback, consistency, non-destructive operations, discoverability, scalability and reliability are identified. Rather than the use of the arbitrary company interface design guidelines, Norman advocates the return to well-established usability guidelines based on solid principles of interactive design.
To assess the quality of an interface, it is helpful to consider five components of usability identified by Nielsen (2003).
1. Learnability is determined by task accomplishment of first time users.
2. Efficiency is task achievement by familiar users.
3. Memorability is re-established proficiency after not using a device.
4. Errors identify the frequency, severity and recovery of interruptions.
5. Satisfaction indicates how pleasant the design is to use.
Most of the issues identified by Norman relate to efficiency and errors and include inconsistency with commands and unexpected quits. Consequently learnability is influenced for first time users. In addition, memorability is influenced, particularly where different applications require the learning of new sets of commands. Many of the challenges are a consequence of the ambitious goal to transition from traditional keyboard and mouse input devices to the gestural interfaced devices where menus are often absent. The need for sound design principles in this context is increasingly important.
Norman’s suggestion that gestural interfaces are a step backwards in usability is less compelling. It was also unclear why he indicated why the interface systems under threat. Human computer interface has a history of being far from optimum, yet computers have still contributed significantly to increased human productivity and continued improvement in their usability is evident. The first IBM personal computers were supported by Microsoft’s acquired QDOS, a quick and dirty operating system designed for enthusiasts and hobbiest but not for release to the public (Deepak, 2001). Yet despite this heritage, improvements relating to technology usability are well documented. iPhone App users are described as suffering less misery and being happier that regular web users (Nielsen, 2010b). The first impressions from many iPad app users describe the interfaces as ‘beautiful’ compared with not-app web user descriptions of web pages as ‘busy’ (Nielsen, 2010a). This suggests that reasonable degrees of usability satisfaction is being experienced (Nielsen, 2003).
The evolving nature of human computer interfaces would suggest that an optimum state of usability could be difficult to attain with initial implementation of an innovation that provides a different paradigm of interaction, as is the case with gesture-interfaced devices. According to Nielsen (2011), the usability evaluation of the iPad one year after its release, indicates that the focus of its use was still evolving. As with any new device, defining a representative user can be problematic, making it difficult to evaluate. In the case of the iPad there are uncertainties as to whether its primarily use is leisure, productivity, or both. Ambivalence also exists as to whether it is more likely to be used by a single user of by multiple users. It is also important to recognise that a complete set of design guidelines is still evolving (Nielsen, 2011). The interface challenges are more complex considering the multimedia elements present and the increased number of options available to developers (Nielsen in Sutcliffe, Kurniawan, & Shin, 2006). In defense of developers, it is appropriate to recognize that not all guidelines have been tested and are not necessarily easy to apply on a commercial scale (Sutcliffe, et al., 2006).
The article appears to understate the complexity of these devices and how much progress has been made, due largely to compliance with existing design principles. With new paradigms, Nielsen (2010b) identifies the need for a sufficiently different interface, not one ported from a previous old paradigm. There is evidence that this has occurred with gesture-interfaced devices. The number of displayed objects is reduced to adjust from mouse or stylus pointing to finger pointing. Additional space is provided between objects as part of the design to provide the necessary touch zones. Future applications incorporating appropriate usability elements will see dynamic news media, adjustable manipulative and personalized data visualizations that will revolutionize how we interact with media. Natural actions of novel gestural movements are sure to accompany these innovations (Prekopcsk, Halcsy, & GsprPapanek, 2008).
Usability testing is recommend and is most beneficial in the design phase of development (Reeves & Hedberg, 2008). However, rapidly changing technologies result in considerable pressure that may prevent time consuming laboratory testing when competitive advantage is gained by the early release of technology innovation. The challenge will be to provide the exploration and testing required to maintain optimum levels of usability.
Reference List
Nielsen, J. (2010a). iPad Usability: First Findings From User Testing. Retrieved 26 August, 2011, from http://www.useit.com/alertbox/ipad-1st-study.html
Nielsen, J. (2010b). iPhone Apps Need Low Starting Hurdles. from http://www.useit.com/alertbox/mobile-apps-initial-use.html
Nielsen, J. (2011). iPad Usability: Year One. Retrieved 26 August, 2011, from http://www.useit.com/alertbox/ipad.html
