A growing area of research concerns the increasing use by young people of mobile phones. Inevitably, researchers interested in exploring the lives and habitus of young people must also consider their engagement with the ubiquitous mobile. This research, however, can create a number of ethical dilemmas, some that are already discussed in literature on internet use and ethics, but also others that are more specifically related to mobile usage, such as the trail left by the data from mobile technologies, and the inclusion of third parties in research without explicit permission. This article discusses the ethical dilemmas arising in this research with young people; it indicates how these dilemmas may challenge current research ethics guidelines and provides recommendations for ethical research in these situations. (Contains 1 table.)