Even though participatory budgeting has spread to more than 1700 cities worldwide, and ICTs are increasingly being used to support participatory budgeting processes, technology has not been used in these scenarios to particularly foster peace outcomes. In this context, the presentation discusses the results of a participatory research for action project in Medellín, Colombia, to design, pilot and refine a participatory budgeting game and tech tool, to foster peace outcomes in this city, such as social inclusion, transparency, empowerment and trust in governmental processes. The project is part of a PhD research at the Centre for Socio-Legal Studies, supported by the Skoll Centre For Social Entrepreneurship at the University of Oxford and the Build Peace Fellows Programme.