Performance comparison between the preferred right and preferred left hands in text entry using Qwerty touch keyboard smartphones

In one-handed text entry with a smartphone, we investigate whether the use of the preferred hand presents better performance than when the non-preferred hand is used. In particular, we study whether the performance of a skilled left hand is worse than that of a skilled right hand among right-handers. A total of 30 young, male, right-handed undergraduate students participated in the experiment. Half of the participants preferred to use their right hands for the smartphone text entry when only one hand was available, whereas the other half preferred to use their left hands. The participants were instructed to type a text message using a Qwerty touch keyboard with both hands, with right hand only, and left hand only through three different experiments. The text completion time and number of errors were measured, and words per minute and keystrokes per minute were calculated to compare the performance among the text entry tasks. In entering a text message with only one hand, approximately 70% of the 15 participants who preferred to use their right hands and approximately 30% of the other 15 participants who preferred to use their left hands have shown to perform better when using their preferred hand than when using their non-preferred hand. The performance of the participants with a skilled left hand was not worse than that of those with a skilled right hand in smartphone text entry. Text entry is one of the most problematic tasks in smartphones, and the usability testing of text entry is necessary to improve the performance of this task. This study addresses a number of basic questions on the selection and screening of participants for the usability testing of smartphone text entry. •We compare the performance of one-handed text entry in smartphones between the preferred and non-preferred hand.•Use of the preferred hand does not guarantee better performance than using the non-preferred hand.•We compare text entry performance between skilled right and skilled left hand among right handers.•There is no significant difference in one-handed text entry performance between skilled left and skilled right hand.