YoYoApp is a native mobile application designed for sports coaches, such as those in American football, basketball, and other athletic disciplines. The app aims to streamline the process of creating, managing, and recording results for the Yo-Yo test (also known as the 20-meter shuttle run test, beep test, or bleep test). It allows coaches to assign athletes to a test and record results in real time during the test, even with around 15 athletes participating simultaneously. The app also facilitates easy sharing of results with athletes, their parents, or other stakeholders.