Deliberative processes in public participation in urban design and decision-making focus on making decisions based on argumentation and a shared notion of the common good (Cohen, 2005), instead of aggregating prefixed preferences as large-scale digital participation platforms frequently do. However, empirical research has shown that deliberation processes risk failing due to challenges of communication and comprehension (Bächtiger and Beauvais, 2016). As deliberation is based on the presentation of arguments, different gaps in subjects’ positions and backgrounds lead to unequal opportunities to shape deliberative processes (Rosenberg, 2007, 2014). We argue that the informed use of specific technological devices here referred to as situated digital citizen participation technologies, can mitigate inequality in deliberative citizen participation practices. The study indicates avenues for future research on deliberation-supporting technologies by proposing a dual focus on (1) immersive and shared spaces and (2) interactive visualization techniques.