This study assesses the MIT App Inventor's effectiveness in instilling Computational Thinking and Generative AI skills through a five-day workshop focused on mobile app development. With its block-based coding system, App Inventor proved to be user-friendly, significantly enhancing programming accessibility for beginners. Participants experienced a marked increase in confidence and expressed enthusiasm for applying these new skills in real-life contexts, exemplifying the principles of Computational Action. The results underscore the potential of App Inventor as a valuable educational resource, fostering technical aptitude and innovation among an international array of students.