Tech Report HCIL-91-12

Plaisant, C., Sears, A. (Sept. 1991)
Touchscreen interfaces for alphanumeric data entry
Proc. of the Human Factors Society - 36th Annual Meeting, vol. 1, (Atlanta, GA, Oct. 12-16, 1992) 293-297. Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 195-204. Also Human Factors Perspectiv es on Human-Computer Interaction, Selections from Proc. of Human Factors and Ergonomics Society Annual Meetings 1983-1994, Perlman, G., Green, G.K., Wogalter, M.S., Eds. (1995) 261-265.
HCIL-91-12, CS-TR-2764, CAR-TR-585

In cases when only limited alphanumeric data must be entered, or when layout, labeling, or size may be changed, traditional keyboards may not be optimal. A series of experiments has demonstrated the usability of touchscreen keyboards. We give a summary of the existing data concerning the usability of touchscreen keyboards including typing rates for experts and novices on keyboards of various sizes. We also report on a recent study done with representative users. Results indicate that typing rates inc rease rapidly reaching peak performance after only 25 minutes of use. Practical suggestions for the design of such a keyboard are also presented.