An Integration of User-Centered Design and Design Thinking Principles for Developing a Mobile Application for Nutritional Tracking for Thai Elderly: A Mixed-Method Study

The growing elderly population presents significant challenges for health and nutrition management, particularly in maintaining dietary balance and nutrient intake. This study aims to develop a mobile nutrition calculator application tailored to elderly users by integrating User-Centered Design (UCD) and Design Thinking methodologies. The research employs a mixed-method approach comprising five phases: context analysis, requirement specification, user modeling, interface design, and usability testing. A total of 30 elderly participants were engaged through interviews, prototyping, and usability testing. Findings highlight critical usability issues specific to the elderly, including visual, cognitive, and interactional limitations. The application was developed using Kotlin and Firebase, with interface elements designed via Figma to ensure clarity and accessibility. Usability results showed high satisfaction (Mean=4.42, SD=0.51) and effective user engagement, with the integrated design approach outperforming conventional development strategies. This study contributes a practical framework for age-friendly digital health design, emphasizing the synergistic strengths of UCD and Design Thinking in addressing elderly-specific usability needs. The findings offer insights for developers, researchers, and health practitioners seeking to improve digital health tools for aging populations.