There has been a growing interest in the fields of Psychology and Human- Computer Interaction (HCI) to develop interactive technologies to facilitate the practice of mindfulness, which has shown significant benefits for physical and mental wellbeing. However, there has been limited academic work evaluating the distinct approaches taken from both fields, and in what way they could benefit each other. In this paper, we present a scoping review of interactive biofeedback mindfulness technologies for enhancing mental wellbeing. We performed a literature search using the main academic databases in Psychology and HCI, retrieving all papers written in English and published since the beginning of the literature until January 2020. This abstract presents preliminary findings from the analysis of 131 articles (the initial search elicited 236 articles, from which 105 duplicates were identified and removed). We aim to contribute in three ways: (1) by providing a scoping review of interactive mindfulness technologies for mental wellbeing, (2) by presenting a comparative analysis of the design considerations taken to highlight the gaps and opportunities between the approaches in psychology and HCI, and (3) providing implications for designing such technologies to enhance mental wellbeing.