Design a comprehensive, step-by-step course outline for junior users to learn how to create mobile applications using React Native. The course should include fundamental concepts of app development, hands-on projects, and practical exercises. Please incorporate beginner-friendly resources, such as tutorials and documentation, to facilitate the learning process. The course should aim to take users from basic understanding to building a fully functional mobile application by the end of the program. Include suggested milestones and key learning outcomes for each module.