As mobile access and massive open online courses (MOOCs) become a global reality, the realm of potential distance learners is expanding rapidly. Mobile learning (mLearning) as well as MOOCs are based on similar characteristics as shown in the literature review of this study. They both enhance a community feeling, increasing networking and collaboration; they strengthen lifelong and informal learning, they use social media to a large extend and they are ideal for setting up communicative dialogues. The focus on learner interactions is of interest, as research has shown that dialogue is an important element for learning and knowledge enhancement, and mobile access increases the opportunities to enter into such interactions. This thesis study used a sequential explanatory mixed methods approach to investigate the impact of mobile accessibility on learner interaction in a MOOC. The study showed that opening up a MOOC for mobile access has immediate impact on learner interactions, as participants with mobile devices tend to interact more with their fellow learners in comparison to their non-mobile colleagues. This was deduced from the mixed methods approach looking at web-based statistics, an online survey, an analysis using the Community of Inquiry framework and one-on-one interviews with volunteers. The study formulated a set of 20 strategies and possible consequences deriving from the analysis of the impact of mobile accessibility in a MOOC and more specifically how this affects learner interactions. These strategies might optimize the impact of mobile access on learner interactions in an informal, open, online course. Future research needs to support the findings, embracing a larger learner population from a more varied background. Overall, this research hopes to add to the body of knowledge strengthening the field of distance education.