It is very important to improve the design of the real-time operating system (RTOS) especially if we want to use it in some special devices. Numerous researches have accepted conventional RTOS as being the customary approach for designing devices used by children. This is because these are able to facilitate the implementation different criteria such as clustering, stability and alternate programs. In this paper, numerous publications have been analyzed to observe the performance of the RTOS when it is subjected to varied constraints. The study focuses on a review of RTOS in relation to play models to analyze their capabilities on various computing platforms and OSs. The publications which we have collected have been sorted out to comprehensively review thereby leading to the configuration of several factors affecting the features within the system. Likewise, statistics and results have facilitated adoption of a more focused approach towards the development of RTOS. While this program ranks clustering and performance as being the highest RTOS criteria for all applications, alternate programs considered this to be the least important. Thus, criteria choice becomes an important issue to address. Key words: Operating system (OS), play model, real-time, real-time operating system (RTOS) performance, RTOS criteria.