The new sociocultural perspectives of Second Language Acquisition suggest that cognitive and language development arises through social interaction. Engaging students in language production tasks that focus on both form and meaning simultaneously fosters natural language use and learning. Social media has emerged as a promising tool to support language learning, offering a 24 × 7 social networking space where language practices extend beyond the classroom. This chapter outlines our decade-long research studies on seamless Chinese learning supported by social media. Seamless learning involves a continuity of learning across different locations, times, technologies, or social settings, intentionally connecting different forms of language learning efforts for deeper learning. Informed by the design principles of seamless learning, we designed and implemented iterative seamless Chinese learning processes in local schools, starting with classroom teaching and extending to mobile device use for creating social media content (photos and Chinese captions related to their daily lives) in Chinese. Their works are then shared, discussed, and reviewed on social networks, supplemented by periodic in-class peer reviewing activities facilitated by teachers. This chapter discusses the rationale behind developing various seamless Chinese learning models, illustrating the evolution of research inquiry and techno-pedagogical designs, and their impacts on students’ language learning experiences, teachers’ professional development and school practices.