Finger-Based Pointing Performance on Mobile Touchscreen Devices: Fitts’ Law Fits
In this paper we investigate the utility of Fitts’ law for predicting the performance of finger-based pointing on mobile touchscreens, by taking into account both different screen sizes and appropriate interaction styles. The experimental design bases on randomly generating pointing tasks in order to provide a wider range of both suitable target sizes and required finger movements, thus targeting a better representation of common pointing behavior with respect to the usual static test design with a smaller set of predetermined tasks. Data obtained from the empirical study was evaluated against Fitts’ law, specifically its revision which defines target size as the smaller dimension of a 2D shape. Results show a strong model fit with our data, making the latter a fair predictor of pointing performance on mobile touchscreen devices. Altogether ten finger-based pointing models are derived, revealing Fitts’ law pragmatic utility regarding various mobile devices, interaction styles, as well as real target sizes commonly found in mobile touchscreen interfaces.
KeywordsFitts’ law Pointing performance Mobile devices Touchscreens Finger input
The work presented in this paper is supported by the University of Rijeka research grant Grant 13.09.2.2.16.
- 3.MacKenzie, I.S., Buxton, W.: Extending Fitts’ law to two-dimensional tasks. In: Proceedings of SIGCHI Conference on Human Factors in Computing Systems (CHI 1992), pp. 219–226. ACM Press, New York (1992)Google Scholar
- 4.Welford, A.T.: Fundamentals of Skill. Methuen, London (1968)Google Scholar
- 5.Accot, J., Zhai, S.: Refining Fitts’ law models for bivariate pointing. In: Proceedings of SIGCHI Conference on Human Factors in Computing Systems (CHI 2003), pp. 193–200. ACM Press, New York (2003)Google Scholar
- 6.Oel, P., Schmidt, P., Schmitt, A.: Time prediction of mouse-based cursor movements. In: Proceedings of Joint AFIHM-BCS Conference Human-Computer Interaction (IHM-HCI 2001), vol. II, pp. 37–40. Cépaduès-Éditions, Toulouse (2001)Google Scholar
- 9.Albinsson, P., Zhai, S.: High precision touch screen interaction. In: Proceedings of SIGCHI Conference on Human Factors in Computing Systems (CHI 2003), pp. 105–112. ACM Press, New York (2003)Google Scholar
- 10.Sasangohar, F., MacKenzie, I.S., Scott, S.D.: Evaluation of mouse and touch input for a tabletop display using Fitts’ reciprocal tapping task. In: Proceedings of 53rd Annual Meeting of the Human Factors and Ergonomics Society (HFES 2009), pp. 839–843. Human Factors and Ergonomics Society, Santa Monica (2009)Google Scholar
- 12.Bi, X., Li, Y., Zhai, S.: FFitts law: modeling finger touch with Fitts’ law. In: Proceedings of SIGCHI Conference on Human Factors in Computing Systems (CHI 2013), pp. 1363–1372. ACM Press, New York (2013)Google Scholar
- 13.Okada, H., Akiba, T.: Fitts’ law index of difficulty evaluated and extended for screen size variations. In: Matrai, R. (ed.) User Interfaces, pp. 229–238. InTech, Rijeka (2010)Google Scholar
- 14.Android Developers: Iconography. http://developer.android.com/design/style/iconography.html
- 15.Android Developers: SystemClock. http://developer.android.com/reference/android/os/SystemClock.html