The emerging paradigm of mobile open social learning for languages (MOSL4L) integrates the three elements of mobile, open and social, and in so doing it creates the idea of a conceptually different language learning space. It is a space full of opportunity and challenge, relevant to a post-pandemic world in which we are looking for ways to build back better. The paper discusses tensions between formal and informal language learning and the nature of learning outcomes in MOSL4L. It focuses on the needs of individuals while also considering the characteristics of the virtual spaces in which they participate. It highlights the potential of micro experiences and learning moments as structures that are well aligned with MOSL4L. It suggests developments in language curricula to take account of communication challenges being identified in the contemporary world. Many more new learning designs and software architectures will have to be developed to match the possibilities generated by the MOSL4L space.