Author: Hrvoje Benko, Daniel Wigdor
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