Design Strategies for GUI Items with Touch Screen Based Information Systems: Assessing the Ability of a Touch Screen Overlay as a Selection Device

Touch screens are a popular method of interaction with information systems embedded in public kiosks. Typical information systems are used on desktop PCs and therefore restricted to having a mouse as the selection device used to interact with the system. The purpose of this paper is to investigate how effective a touch screen overlay is in selecting typical graphical user interface (GUI) items used in information systems. A series of tests were completed involving multi-directional point and select tasks. A mouse, being the standard selection device, was also tested so the results of the touch screen could be compared. The GUI items tested were a button, check box, combo box and a text box. The results showed that the touch screen overlay was not suitable in terms of selecting small targets with a size of 4mm or less. The touch screen overlay was slower and had higher error rate compared to the mouse. There was no significant difference in throughput between a touch screen overlay and mouse. The mouse was rated easier to use and easier to make accurate selections with. The touch screen had higher arm, wrist and finger fatigue. This indicates that a touch screen overlay used only with a finger is not a practical selection device to use with interfaces containing small targets.