These proceedings contain the papers and posters of the 15th International Conference on Mobile Learning 2019, which was organised by the International Association for Development of the Information Society and co-organised by the University of Applied Sciences, in Utrecht, The Netherlands, April 11-13, 2019. The Mobile Learning 2019 Conference seeks to provide a forum for the presentation and discussion of mobile learning research which illustrate developments in the field. In particular, but not exclusively, these proceedings aim to explore the theme of mobile learning under the following topics: (1) Learning analytics and mobile learning; (2) Cloud computing and mobile learning; (3) Pedagogical approaches, models, and theories for mLearning; (4) mLearning in and across formal and informal settings; (5) Strategies and challenges for integrating mLearning in broader educational scenarios; (6) User Studies in mLearning; (7) Learner mobility and transitions afforded by mLearning; (8) Socio-cultural context and implications of mLearning; (9) Mobile social media and user generated content; (10) Enabling mLearning technologies, applications, and uses; (11) Evaluation and assessment of mLearning; (12) Research methods, ethics, and implementation of mLearning; (13) Innovative mLearning approaches; (14) Tools, technologies, and platforms for mLearning; and (15) mLearning: Where to next and how?