This paper presents a comparative study of the Waze avoid areas (WADA) feature in Jerusalem, Rio de Janeiro, and the US. I argue that, through comparative approaches, geographers can 'ground' the digital, developing situated accounts of how emerging technologies work at different sites. Taking as a starting point the controversies raised by WADA, I address the following research questions: How does the feature work in the three research sites? What political problems does it raise? What are its effects? Drawing on 124 news articles, blog posts and forum threads in English, Arabic, Hebrew and Portuguese, the analysis complicates existing characterisations of similar apps as emblematic of the smart city's most oppressive characteristics, pointing at three themes: the relevance of local settings in the enactment of WADA, the interplay of different logics in its definition of danger, and the heterogeneity of public reactions to the app. More broadly, the study demonstrates that grounded comparative studies can decentre and enrich the scholarship on digital geographies, underscoring the contingency and ambivalence of digital technologies.