Rapid urbanization, climate change, resource depletion, the wish for a more sustainable development and the widespread use of the Internet and mobile phones all represent a great challenge for urban planning. While the smart city model is seen as a means to cope with these challenges, it is often reduced to an amalgam of technologies. Citizens are usually left outside the planning process, although they produce a massive amount of data related to how they live and use the city. Applying the smart city model demonstrates that digital technologies deeply change urban management systems. These technologies also create an opportunity to reshape the planning process by generating new forms of interaction between urban planners and city dwellers, which become useful tools for sustainable and responsive planning. This research explores how these new tools can be harnessed to enhance citizen involvement in the planning process.