In this paper I discuss some of the ethical issues relating to the use of mobile technologies in education. I argue that the frames of reference used by educators and technologists typically fail to capture the nature, scope and impact of ethical issues in mobile learning. Part of the problem is that the right kind of analytical tools for research into ethics. I propose a taxonomy of ethical issues based on dominant positions in meta-ethical theory, suggesting that we need a reconstructive approach which focuses on the responsibilities of students, educators and policymakers; the desirability of the outcomes from mobile learning initiatives; and assessing the learning or development of those involved. Referring to the methodology from the Mobile Technologies in Lifelong Learning (MOTILL) project, I show how an alternative methodological foundation might both affect research design and facilitate understanding of ethical issues in mobile learning. Presented at the Computers and Learning Research Group (CALRG) Conference 2010 (http://kn.open.ac.uk/public/workspace.cfm?wpid=5403)