Older Adults’ Text Entry on Smartphones and Tablets: Investigating Effects of Display Size and Input Method on Acceptance and Performance

Abstract

This study focuses on older adults’ finger-based text entry on smartphones and tablets. Thirty-two older adults entered Chinese characters with two input methods (typing and handwriting) on touch screens with four display sizes (3.5 in., 5 in., 7 in., 9.7 in.). Their performance, acceptance, preference, and errors were recorded and thus four findings were found. First, on small displays (3.5 in. and 5 in.), handwriting contributed to shorter task completion time, higher perceived ease of use, and higher usage intention than typing, but no difference was observed on large displays (7 in. and 9.7 in.). Second, there is a gap of task completion time and perceived ease of use between 5 in. and 7 in. for typing, whereas there is no gap for handwriting. Third, participants’ preference of 9.7 in. was almost the same as that of 7 in., and their preference of 7 in. was 1.5 times as strong as that of 5 in. Fourth, participants’ finger-based text entry was prone to 13 types of errors. Many of these errors were caused by the mismatch between older adults’ mental models and designers’ mental models.

FUNDING

This study was funded by a National Science Foundation China grant 71188001.

Additional information

Notes on contributors

Jia Zhou

Jia Zhou is an assistant professor in the Department of Industrial Engineering at Chongqing University and a visiting research scholar at Trace Center in University of Wisconsin-Madison. Her research focuses on acceptance and usability of mobile devices for older adults.

Pei-Luen Patrick Rau

Pei-Luen Patrick Rau is the Director of the Institute of Human Factors and Ergonomics and Professor in the Department of Industrial Engineering of Tsinghua University in Beijing. He has founded and directs the HCI and Usability Research Center at Tsinghua University.

Gavriel Salvendy

Gavriel Salvendy is a professor emeritus of Industrial Engineering at Purdue University and Chair Professor Emeritus and former Head (2001–2011) of the Department of Industrial Engineering at Tsinghua University, Beijing, P.R. China. He is the author or coauthor of more than 580 research publications, including 320 journal articles, and is the author or editor of 43 books.