Abstract
This paper can be framed within the growing interest in the public dimension of technology design: it proposes a framework for the public design of urban technologies by elaborating on the concepts of digital commons, matters of concerns and engagement. The framework is discussed through the case study of a mobility application developed within a wider project of digital commons design. We contrast a Smart City approach and a urban computing one, and we argue that the latter is more fruitful in the long run, since it entails elements for the establishment of forms of recursive engagement of users, who co-produce digital commons together with technology designers as a response to their matters of concern. Applying our framework to the design of urban technologies, we conclude that design should support collaborative practices starting from the articulation of matters of concern to designing in a participatory way.