PonDeFlick: A Japanese Text Entry on Smartwatch Commonalizing Flick Operation with Smartphone Interface

While the QWERTY keyboard is a standard text entry for Latin script languages on smart devices, it is not always true for non-Latin script languages. In Japanese, the most popular text entry on smartphones is a flick-based interface that systematically assigns more than fifty kana characters to twelve keys of a numeric keypad in combination with flick directions. Under these circumstances, studies on Japanese text entry on smartwatches have focused on an efficient interface design that takes advantage of the regularity of the kana consonant and vowel structure, but overlooked commonality with familiar interfaces. Thus, we propose PonDeFlick, a Japanese text entry that commonalizes the flick directions with the familiar smartphone interface while providing the entire touchscreen for gestural operation. A ten-day user study showed that PonDeFlick reached a text-entry speed of 57.7 characters per minute, significantly faster than the numeric-keypad-based interface and a modification of PonDeFlick without the commonality.