This article provides feedback on a multidisciplinary and applied research project to design a data mapping and exploration tool on Twitter for journalists. The approach focuses on the observation and understanding of journalists' uses and a projection of the integration of the software in their daily practices and routines. Three use cases scenarios are explored, reflecting the diversity of the tool's appropriation. Each of them underlines the interest in designing a transparent interface that favors the user's understanding of the operations performed on the data, but also the need for users to have a minimal digital culture to produce journalistic content based on these digital traces.