Journal of Graphic Engineering and Design

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Vol. 16 No. 1 (2025): JGED - March 2025
Preliminary report

Enhancing accessibility of Thai government mobile applications through effective use of typefaces, type sizes, and colour contrast: A technical review

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  • Rachapoom Punsongserm,
  • Pittaya Suvakunta
Rachapoom Punsongserm
Thammasat University, Faculty of Fine and Applied Arts, Pathum Thani, Thailand; Thammasat University, Thammasat University Research Unit in Social Design, Pathum Thani, Thailand
Pittaya Suvakunta
Thammasat University, Bangkok, College of Interdisciplinary Studies, Thailand; Thammasat University, Thammasat University Research Unit in Social Design, Pathum Thani, Thailand
DOI: https://doi.org/10.24867/JGED-2025-1-017

Published 2025-02-06

abstract views: 28 // Full text article (PDF): 25


Keywords

  • accessible typography,
  • Thai typeface,
  • font size,
  • colour contrast,
  • mobile application

How to Cite

Punsongserm, R., & Suvakunta, P. (2025). Enhancing accessibility of Thai government mobile applications through effective use of typefaces, type sizes, and colour contrast: A technical review. Journal of Graphic Engineering and Design, 16(1), 17–37. https://doi.org/10.24867/JGED-2025-1-017

Copyright (c) 2025 © 2025 Authors. Published by the University of Novi Sad, Faculty of Technical Sciences, Department of Graphic Engineering and Design. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license 3.0 Serbia

Creative Commons License

This work is licensed under a Creative Commons Attribution 3.0 Unported License.

Abstract

This study reviewed the legibility of Thai typefaces, type sizes, and colour contrast in mobile applications provided by Thai government offices. Although the Electronic Government Agency (Public Organization) (EGA) has introduced the Government Website Standards and Government Mobile Application Standards, these standards need to cover the design of Thai typographical concerns such as legibility and visibility in great detail. This study aimed to identify typographical issues that may arise in these mobile applications and gain a deeper understanding of the subject matter. The findings of this study could lead to future investigations that provide a better understanding of the topic and contribute to the development of appropriate standards and legislation. We conducted an in-depth analysis of Thai Government mobile applications on Android focusing on public service areas. Using a smartphone to take screenshots and a vector graphics design program to measure physical type sizes based on the Bo Baimai height measurement, we measured the use of typefaces, type sizes, and colour contrast to ensure accessibility to all users. Additionally, we used a colour contrast analyser application to measure colour contrast and ensure accessibility to all users. Our study provides insights to improve user experiences with these applications and highlights that Thai web and mobile standards lack suitable fonts and sizes. We identified two main categories of Thai typefaces: conventional text fonts and Roman-like Thai fonts. Most Thai mobile applications used letter sizes bigger than 1.2 mm in Bo Baimai height, but some used smaller sizes, which could be worse for reading. The smallest type sizes for body text ranged from 1 to 1.7 mm. Regarding contrast ratios, we found that regular text in selected mobile applications did not meet the Web Content Accessibility Guidelines (WCAG) 2.1 enhanced contrast requirement of a 7:1 ratio. However, some contrast ratios for large text met the 4.5:1 requirement. Some regular text with a 4.5:1 contrast ratio requirement passed the WCAG 2.1 minimum contrast test, whereas some large text with a 3:1 contrast ratio requirement also met the criteria. Our study suggests the need for developing better standards and regulations for Thai fonts, sizes, and colour contrasts in mobile applications to ensure accessibility for all users.

Article history: Received (July 27, 2023); Revised (February 12, 2024); Accepted (March 11, 2024)

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