Glass+Skin: An Empirical Evaluation of the Added Value of Finger Identification to Basic Single-Touch Interaction on Touch Screens

Abstract

The usability of small devices such as smartphones or interactive watches is often hampered by the limited size of command vocabularies. This paper is an attempt at better understanding how finger identification may help users invoke commands on touch screens, even without recourse to multi-touch input. We describe how finger identification can increase the size of input vocabularies under the constraint of limited real estate, and we discuss some visual cues to communicate this novel modality to novice users. We report a controlled experiment that evaluated, over a large range of input-vocabulary sizes, the efficiency of single-touch command selections with vs. without finger identification. We analyzed the data not only in terms of traditional time and error metrics, but also in terms of a throughput measure based on Shannon's theory, which we show offers a synthetic and parsimonious account of users' performance. The results show that the larger the input vocabulary needed by the designer, the more promising the identification of individual fingers.

Quantifying Differences among Ten Fingers in Force Control Capabilities by a Modified Meyer Model

“…Results from Antal et al [46] showed that these additional features enhance the accuracy of both processes. Hereby, these studies suggested a heuristic supporting the pattern analysis and recognition of tapping fingers by checking responding finger of each typing, similar to fingerprint identification [47,48]. Keystroke dynamics of finger force control for user authentication has become an active research area due to its low cost and ease of integration with existing security systems.…”

Characterizing Finger Pitch and Roll Orientation During Atomic Touch Actions

“…Colley et al [3] and Goguey et al [7] compared their performance as well as users' preferences in Fitts' tasks. Roy et al also looked at their reaction times and error rates [28]. Finally, Wang et al evaluated the precision of different fingers in a tapping task [34].…”

Leveraging finger identification to integrate multi-touch command selection and parameter manipulation

“…Recent studies show that even for single-touch command selection, finger identification is a promising solution to increase the touch input vocabulary [14]. Robust finger identification sensing is on the horizon [15,16], but examples of the interaction it enables have only been isolated point designs without cohesive design.…”