This paper describes some of the findings emerging from a small-scale pilot study investigating the potential of a tablet app, Our Story (Ar Stoiridh), to enhance language-learning opportunities for children in Gaelic-medium preschool playrooms. The intervention drew on design-based research, a methodology for investigating the relationships among educational theory, designed artefact and practice. A significant feature of this approach is the close collaboration between researchers and practitioners in identifying the problem to be addressed by the intervention and refining, through successive iterations, the solution. Detailed documentation of the process enables the researchers to keep track of practical barriers or facilitators, and often leads to design changes. In this case, it emerged that there were marked differences between the researchers' and the practitioners' beliefs about effective language learning in the early years, a finding which would have had a bearing on the development of the design beyond the pilot phase. It is argued that this finding has implications for theoretical understanding of how preschool practitioners set about supporting children as they learn a new language in immersion-style settings; and of how to design practical interventions, such as the use of digital technologies to support early language learning or professional development for preschool practitioners in such settings. (author abstract)