This article draws on original, empirical research that focused on the use of an experimental mobile application developed by the authors and used in the domain of youth justice in England. Against a backdrop of the theory of the paradox of technology with ideas of the networked self and child rights, the article explores the use of social technology with vulnerable/marginalised young people. Given the dearth in knowledge and understanding, in this area of social technology and young people in conflict with the law, the article focuses on an important, original and fast-developing issue in contemporary youth justice. Principally, the article explores the experiences and views of practitioners to promote a better understanding of the opportunities and challenges in the adoption of social technology in working with marginalised young people. Practitioner perceptions on the use of social technology in their own practice and its associated risks and benefits are also revealed. Study findings indicate that digital opportunities and challenges are embedded in organisational and cultural structures and practices. The article discusses implications for youth justice and ultimately for young people in conflict with the law who are caught up in the system. The article raises important issues about the likely increasing use of technology as a tool in rehabilitation and desistance; and its key messages will be of considerable interest to practitioners, managers and policy-makers who will have little option, as time goes on, to enter this controversial field.