app developer to introduce an interesting, complex, or impressive experience to the user (e.g., a puzzle or action) without making it difficult to learn and discover.
User-Centered Design Jeff Bos, Design Insights BlackBerry
Overview • Real World Design Challenges – UX Design Principles
• Cognitive Demand – Techniques for reducing workload
• Discount Usability Techniques – Best practices for product design
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What is Usability? ISO 9241-11 outlines three objective factors for measuring the usability of a product: 1. Speed: Users’ efficiency when carrying out tasks. 2. Accuracy: Users’ effectiveness when interacting with the system. 3. Satisfaction: Users’ satisfaction when experiencing the design.
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Real World Design Challenges How do you adjust the following controls?
1. Heated Mirrors
2. Volume Control
3. Parking Brake
Real World Design Challenges Answers:
1. Heated Mirrors
2. Volume Control
3. Parking Brake
What is Affordance?
Discoverable Design “Fewer people than ever read manuals.” – This is true whether it is a manual for an automobile, a new cooking device a TV set, a computer program or app, or a game. – Therefore, the important point is to develop devices that are self-explaining, that do not require manuals. – In the new edition of Design of Everyday Things Don Norman calls this property, “Discoverable”.
Discovery-Based Learning “People just want to use a product.” – As a metaphor for UX design, consider the challenge of telling the backstory in a novel or detective/crime/spy story. – The author has to bring the reader up to speed without losing the narrative flow of the story or losing the reader’s attention. – As a device, the author will introduce a new character to the scene, so that either the hero has to explain a lot of stuff (in a natural way), or the new person will unearth material and rush to tell others.
Successive Approximations “People just want to use a product.” – Successive Approximation is a technique that can enable a app developer to introduce an interesting, complex, or impressive experience to the user (e.g., a puzzle or action) without making it difficult to learn and discover. – A practice case can be used to make the challenge as approachable as possible without compromising the first experience using the feature.
Maximize Cognitive Bandwidth “User attention is a precious resource and should be allocated accordingly. Minimize Visual, Auditory, Psychomotor, and Cognitive load.” 1. Reduce visual noise 2. Build on existing mental models
3. Enable discovery 4. Chunk content 5. Off-load tasks
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Familiarity
Discovery
Consistency
Repeating Patterns
Re-Use
Apprehension and Congruity
Center of Mass The mass of the device should be centralized within the hand – –
In particular, on tall devices, a lower center of mass helps users stabilize the device to prevent wobbling when typing. As the Pivot Point moves toward the Centre of Mass, the torque becomes lower which reduces grip effort and increases device stability when typing.
Optimal Resting Posture and Reach Device Height and Width • As the device gets wider, users have difficulty reaching across the screen • As the device gets taller, users find it more difficult to reach content at the top of the screen and less stable in the hand when typing
Device Thickness [Galaxy Note 2 feedback] • Thinner devices tend to have sharper edges which can dig into the hand • Extra pinch grip force is required to stabilize a thinner device in the hand
Discount Usability Techniques • Heuristic Review – Subject Matter Expert Review – Cognitive Walkthroughs – Critical Incident Technique
• Rapid Prototyping and Usability Testing – A-B Benchmark Testing – Instrumented Software
Nielsen’s Ten Usability Heuristics 1. Visibility of system status 2. Match between system and the real world 3. User control and freedom 4. Consistency and standards 5. Error prevention 6. Recognition rather than recall 7. Flexibility and efficiency of use 8. Aesthetic and minimalist design 9. Help users recognize, diagnose, and recover 10. Help and documentation
Baseline Experience
Visibility of system status Match between system and the real world User control and freedom Consistency and standards Error prevention Recognition rather than recall Flexibility and efficiency of use Aesthetic and minimalist design Help users recognize, diagnose, and recover from errors
First Automated Thermostat 1. It Is Not Transparent –
Not responding as expected
2. People wearing coats in apartment –
Physical discomfort
3. Took Away My Control – –
Turning dial does nothing It doesn’t seem possible to change the temperature at all using the mobile app.
4. Makes Me Feel Stupid –
Difficult UI to tune the system using PC
5. Makes It Difficult to Recover – –
Makes user look bad Guests think owner is deliberately keeping apartment too cold
6. Beauty Is Only Chrome Deep –
High initial expectations lead to a great deal of disappointment
Applying the Heuristics • Visibility of System Status: It is not transparent –
Not responding as expected
• Error Prevention: People wearing coats in apartment –
Physical discomfort
• User Control and Freedom: Took away user control – –
Turning dial does nothing It doesn’t seem possible to change the temperature at all using the mobile app.
• Match Between System and the Real World: Makes user feel stupid –
Difficult UI to tune the system using PC
• Help Users Recognize, Diagnose, and Recover from Errors: Difficult to recover – –
Makes user look bad Guests think owner is deliberately keeping apartment too cold
• Aesthetic and Minimalist Design: Beauty Is Only Chrome Deep –
High initial expectations and lead to a great deal of disappointment
Best Practices in Product Design • Identify Solid Product Requirements: What is unique and compelling about the desired experience? • Tell Your Story: Design your product to have a conversation with your user. Share the value proposition with them and help the make best use of the application. • Intuitiveness and Simplicity: It is difficult to make complex things seem simple. Properly applying UX design techniques makes novices feel like experts. • Iterate Frequently: Be flexible while clearly working out the user experience. Making rapid changes early in the process will reduce time consuming rework later. • Long Wow: Users like product experiences that evolve with them over time.
Summary • Real World Design Challenges – UX Design Principles
• Cognitive Demand – Techniques for reducing workload
• Discount Usability Techniques – Best practices for product design
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