Unlocking Voices: Assessing the Usability and Accessibility of Mobile Applications for Stutter Reduction

Mobile applications for improving speech fluency provide users with a convenient platform to practice speech exercises and build confidence in their communication skills. Since communication disorders typically appear in childhood, these applications are often developed for children with unique accessibility and usability needs. However, existing research overlooks the interdependence of these needs, which presents challenges in designing child-friendly UIs that are both usable and accessible. Therefore, this research aims to assess the usability and accessibility of mobile apps designed for stutter reduction and communication enhancement in children and to investigate their correlations between usability and accessibility evaluation guidelines to address associated issues. To attain these objectives, three randomly selected mobile applications (Speech Jammer, Stamurai, and Penguin) were evaluated using Heuristic Evaluation and Accessibility Evaluation approaches. The study revealed several usability (n=14) and accessibility (n=12) challenges across the evaluated apps. Speech Jammer exhibited the highest number of usability (n=7) and accessibility (n=5) challenges, with an average severity of 2.64, followed by Stamurai and Penguin. The study also found a correlation between usability heuristics and accessibility guidelines, indicating that improving usability issues, such as system status visibility and layout consistency, may enhance the accessibility of the applications. The findings of this research are expected to significantly contribute to future stutter reduction app development by promoting more inclusive and effective UI design.