Cities around the world try to set standards for their digital agendas, and constructing smart city ‘roadmaps’. Taking stock of emerging approaches that seek to apply or supplement existing rules on privacy and data protection and to sustain public confidence and support in the face of innovation and change, challenges are explored. Drawing on a growing critical literature, in law, planning, and other fields, that seeks to identify the nature and implications of these developments beyond the promotional language of ‘smart’, the work of Sidewalk’s masterplan for a site in Toronto, and the Los Angeles Department of Transportation’s new and influential approach to mobility data (data associated with ridesharing, ‘micromobility’ such as e-scooters, and in time autonomous vehicles), is assessed. Two facets of urban technology that relate to (and ultimately enable) the delivery of personalised services by public authorities and others are then considered: ratings and reputation (highlighting Chinese cities deploying aspects of the emerging 'social credit’ systems) and facial recognition (noting that the ability to recognise individuals in this way, without a conventional and more deliberate identification (e.g. supplying a name, entering a password, or older biometric systems such as fingerprint scanning), is a key part of many proposed personalised services).