About: Official Samsung UX Guideline for developers. External vendors that deliver Smart Hub applications use Samsung library to implement casting video from smartphone to TV feature. Guideline helps them to understand the logic. As the demand for such functionality raised, Samsung had to create rules for handling it. Otherwise each vendor would implement its own system, affecting the entire platform. There was a risk that confused users would give up using their smartphone to control the TV. 15 use cases were described.