The exponential growth in technological advancements that benefit children diagnosed with autism has recently occurred. Prior to the growing number of applications to help them communicate, understand, and interact with others, a study on the user interface characteristics, specifically on colour, text, and images in designing mobile application interfaces for children with autism, was conducted to provide preliminary evidence. This study helps in the design and development phase of a mobile application for children with autism. A total of 38 proxy users took part in this study. They were given a questionnaire through an online 5-10 minute survey. The questionnaire comprises questions on the multimedia elements used in designing a mobile application for children with autism. This study aims to identify the user interface characteristics preference, specifically on colour, text, and images, in designing a mobile application interface for children with autism, based on the proxy user perspective. To supplement the body of literature in this area and improve the pedagogical method, the author expresses the related works on the user interface characteristics and usability issues. The enhancement to the instrument used is promising in terms of the mobile application's design and development for children with autism. © 2021 IEEE.