Abstract
Heuristic evaluation has proven popular for desktop and web interfaces, both in practical design and as a research topic. Compared to full user studies, heuristic evaluation can be highly cost-effective, allowing a large proportion of usability flaws to be detected ahead of full development with limited resource investment. Mobile computing shares many usability issues with more conventional interfaces. However, it also poses particular problems for usability evaluation related to aspects such as limited screen real estate, intermittent user attention, and contextual factors. This chapter describes a modified collection of usability heuristics that are designed to be appropriate for evaluation in mobile computing. They have been systematically derived from extensive literature and empirically validated. They therefore offer a sound basis for heuristic-based evaluation in mobile computing. Besides introducing the reader to the practical use of heuristic evaluation, the chapter also closes with a description of potential future research in the area.
keywords: heuristic evaluation, usability evaluation, mobile computing, mobile interfaces, human-computer interaction
The Heuristics
- 1 - Visibility of system status and losability/findability of the mobile device
- Through the mobile device, the system should always keep users informed about what is going on. Moreover, the system should prioritize messages regarding critical and contextual information such as battery status, network status, environmental conditions, etc. Since mobile devices often get lost, adequate measures such as encryption of data should be taken to minimize loss. If the device is misplaced, the device, system or application should make it easy to recover it.
- 2 - Match between system and the real world
- Enable the mobile user to interpret the information provided correctly, by making it appear in a natural and logical order; whenever possible, the system should have the capability to sense its environment and adapt the presentation of information accordingly.
- 3 - Consistency and mapping
- The user's conceptual model of the possible function/interaction with the mobile device or system should be consistent with the context. It is especially crucial that there be a consistent mapping between user actions/interactions (on the device buttons and controls) and the corresponding real tasks (e.g. navigation in the real world).
- 4 - Good ergonomics and minimalist design
- Mobile devices should be easy and comfortable to hold/carry along as well as robust to damage (from environmental agents). Also, since screen real estate is a scarce resource, use it with parsimony. Dialogues should not contain information that is irrelevant or rarely needed.
- 5 - Ease of input, screen readability and glancability
- Mobile systems should provide easy ways to input data, possibly reducing or avoiding the need for the user to use both hands. Screen content should be easy to read and navigate through notwithstanding different light conditions. Ideally, the mobile user should be able to quickly get the crucial information from the system by glancing at it.
- 6 - Flexibility, efficiency of use and personalization
- Allow mobile users to tailor/personalize frequent actions, as well as to dynamically configure the system according to contextual needs. Whenever possible, the system should support and suggest system-based customization if such would be crucial or beneficial.
- 7 - Aesthetic, privacy and social conventions
- Take aesthetic and emotional aspects of the mobile device and system use into account. Make sure that users' data is kept private and safe. Mobile interaction with the system should be comfortable and respectful of social conventions.
- 8 - Realistic error management:
- Shield mobile users from errors. When an error occurs, help users to recognize, to diagnose, if possible to recover from the error. Mobile computing error messages should be plain and precise. Constructively suggest a solution (which could also include hints, appropriate FAQs, etc). If there is no solution to the error or if the error would have negligible effect, enable the user to gracefully cope with the error.
|