Social Sustainability in Smart-City Digital Transformation: Access, Trust, and Participation in Istanbul's Digital Municipal Services

Smart-city research has increasingly moved beyond infrastructure-centered accounts of sensors, platforms, and data analytics toward questions of inclusion, legitimacy, civic capacity, and public value. Building on this shift, this article examines the digital service ecosystem of Istanbul Metropolitan Municipality (IMM) through the lens of social sustainability. The study asks how municipal digital transformation can be evaluated not only as administrative modernization, but also as a socially consequential form of urban governance. Methodologically, the article combines a critical literature review, a document and platform-based case analysis of IMM’s digital service architecture, and a small-scale supporting survey of active users. The conceptual argument is that socially sustainable digital municipalism depends on four mutually reinforcing conditions: equitable access, interactional usability, data-governance trust, and consequential participation. The Istanbul case shows substantial municipal digital capacity through integrated service platforms, mobility applications, public connectivity, online request channels, and open-data infrastructures. The supporting survey, based on 51 valid responses collected between April 29 and May 15, 2026, suggests positive perceptions of access, usability, and overall social benefit, while trust in personal-data security and procedural transparency remains more cautious. Exploratory regression results show that trust is the most robust association with perceived social benefit after access, usability, and participation are considered together. The article contributes to smart-city scholarship by reframing municipal digitalization as a socio-technical governance problem whose success depends less on the number of applications deployed than on the production of inclusion, accountability, and civic confidence