We present a controlled laboratory experiment comparing touch, physical, and touch + overlay (passive finger guide) input for parameter control. Specifically we examined two target acquisition and movement tasks with dial and slider controls on horizontal touch screens. Results showed that physical controls were the fastest and required the least eye fixation time on the controls, while the overlay improved performance when compared to touch alone. Speed and accuracy differences were seen

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... ily for dial controls; there was little difference between input conditions for sliders. These results confirm the value of physical input devices for parameter control tasks. They also reveal that overlays can provide some of the same benefits, making them a suitable input approach for certain applications where physical controls are impractical.