In preparation for the next blog post, the group wanted to take a look at the academics behind designing the user interfaces that people encounter every day, to see why these principles are important. In the next blog post, the group will be showing the prototype designs to see how well the guidelines have been followed.

Design Theory

One commonly used theory in UI (User Interface) design is “Sheniderman’s Eight Golden Rules” [1], which was created to improve the usability of an application by having a well designed UI and good interaction design. The rules are as follows:

1. Strive for consistency – consistent layouts, colours, terminology, commands and sequences of action
2. Enable frequent users to use shortcuts – abbreviations, function keys, hidden commands
3. Offer informative feedback
4. Design dialog to yield closure – sequences of actions should have a beginning, middle and end, and the completion of groups of actions should provide closure
5. Offer simple error handling – design the system to prevent error, and if there is an error provide simple ways to handle it
6. Permit easy reversal of actions – encourages exploration of the interface by reducing anxiety about what could happen as the error can be undone
7. Support internal locus of control – design the system so the user feels that they are controlling it, not responding to it
8. Reduce short-term memory load – keep displays simple, consolidate multiple displays and provide sufficient training

Another design theory commonly used is Nielsen’s 10 Usability Heuristics for User Interface Design [2], and these are:

1. Visibility of system status – keep the user informed with what is happening by providing appropriate feedback within a reasonable time
2. Match between the system and the real world – the system should speak the users’ language with familiar words, phrases and concepts rather than system-oriented terms. Follow real-world conventions to make information appear in a natural and logical order
3. User control and freedom – provide “emergency exit” for leaving unwanted actions and support undo and redo
4. Consistency and standards – follow platform conventions for words, situations and actions to prevent misunderstanding
5. Error prevention – use careful design to prevent errors by eliminating error-prone conditions or check for them and provide users with a confirmation option before they commit to that action
6. Recognition rather than recall – minimise memory load by making objects, actions and options visible, make sure the user doesn’t have to remember information between dialogs and ensure that instructions are visible or easily retrievable
7. Flexibility and efficiency of use – allow users to tailor frequent actions
8. Aesthetic and minimalist design – dialogs should not contain irrelevant or rarely needed information
9. Help users recognise, diagnose and recover from errors – error messages should use plain language, indicate the problem and suggest a constructive solution
10. Help and documentation – whilst it’s best if systems don’t require documentation to be used, any information should be easy to search, focused on the task, not too large and list concrete steps to be completed

As shown, most of these rules match up in some way and are simply there to make life easier for the user, such as preventing frustration when they –  can’t find what they are looking for, or something goes wrong and it simply says, “An error has occurred!”. Good interface design is important in everything – for example, if a user is shopping online, it can be argued that  they are not going to keep visiting a site that makes it difficult to find what they are looking for and creates an error every time they attempt an action.

Whilst these design theories are not the law, simply guidelines, it is still best practice and is becoming continually more championed in the technology world, with big organisations creating their own guidelines and providing accreditation for both usability and accessibility. Further work is also being done to see how these apply specificially to mobile devices, and Gong and Tarasewich [3] look into how Shneiderman’s rules need to be modified, as well as stating their own specific guidelines, (some of which are similar to Nielsen) and these are:

1. Design for multiple and dynamic contexts è allow user to configure to their needs and preferences, including text size and brightness, as well as double, single or no-handed operation
2. Design for small devices – word selection vs text input
3. Design for limited and split attention – sound and tactile output options
4. Design for speed and recovery – allow for applications to be stopped, started and resumed with little or no effort
5. Design for “top-down” interaction – present high-level information and let the user decide whether to view the details
6. Allow for personalisation – provide the users with the ability to change settings to their needs or likes
7. Design for enjoyment – applications should be visibly pleasing and fun as well as usable

Further Reading

As well as design heuristics for interface design, there are also legislation and principles governing usability and accessibility, particularly on the Web, but lots of it can be applied across the board.For example:

• Section 508 of the US Rehabilitation Act – http://www.section508.gov/
• Web Content Accessibility Guidelines (WCAG 2.0) – http://www.w3.org/TR/WCAG20/

This post represents that the group has chosen appropriate economic and social Contextual Factors that directly link to the marking criteria, and are vital to understanding what requirements app design has. This is based on market analysis, evaluation, and expert opinions. There is evidence that research has been chosen intelligently (by reference to literature and analysis) to produce a conclusion of professional quality, leading to a successful product. 

This post additionally represents Engineering and Design decisions. These are based on the Contextual Factors and literature review which the group have tailored the product to incorporate. This means that the app design has considerable research, fluent design and well planned steps to achieve this. This post illustrates how and why the product has been influenced in its design, and shows how engineering this app feature will solve problems, and how the product will further incorporate design decisions. 

References

[1] Shneiderman, B. (1986). Designing the user interface-strategies for effective human-computer interaction. Pearson Education India.

[2] Nielsen, J. (1994). Heuristic evaluation. In Nielsen, J., and Mack, R.L. (Eds.),Usability Inspection Methods, John Wiley & Sons, New York, NY.

[3] Gong, J., & Tarasewich, P. (2004). Guidelines for handheld mobile device interface design. In Proceedings of DSI 2004 Annual Meeting (pp. 3751-3756).

Written by Emily.