main argument
Touch input presents many challenges such as reduced precision, finger occlusion, and lack of clear feedback about interaction states, leading to user frustration and confusion.
conclusion
- Design recommendations
- System designers: implement visualization
- Application designers: provide contextual, unambiguous visual representation and maintain visual consistency
- Implementation: provide visualizations for important states and transitions
- Touch screens must have separate interaction paradigms than mouse input
supporting arguments
- How the application reacts to user input determines how the user will understand the consequences of unexpected behaviors in an application or system
- “relying on individual applications to provide feedback decrease the likelihood of consistency across applications” (251)
- Sources of error and frustration
- Lack of activation notification and haptic feedback 2. Lack of hover state 3. Fat finger problem 1. Occlusion 2. Precision 4. Accidental activation and tabletop debris 5. Non-responsive and captured content 6. Feedback of physical manipulation constraints
- Solutions to the fat finger problem
- Offset cursor
- Vogel and Baudisch’s Shift technique
- Offset small targets from user’s finger
- Widgets
- Touch cursors
- LucidTouch
- Input moved to back of device to eliminate finger occlusion
- LucidTouch
- Dual Finger Selections
- Dual Finger Midpoint
- Dual Finger Stretch
- Dual Finger X-Menu
- Dual Finger Slider
- Challenges in addressing feedback ambiguity
- Visualize action sources, alleviate feedback ambiguity
- Provide clear visual encodings of multiple parameters
- Maintain visual integrity of underlying applications
- Build a framework requiring little work from application developers to leverage
terms and themes
- Touch feedback ambiguity problem
- Little to no application feedback provided to help user deduce the cause of a touch error