A shared photovoice application offers a procedural bridge between situated local accounts and cross-context inquiry, but it does not make urban settings equivalent. Researchers across eight countries used the same digital tool to elicit accounts of public space and physical activity. Their reflections foreground the uneven meanings of safety, conflict and participation and the knowledge co-produced by users, practitioners and researchers. The decisive interface is the annotated image: a selected scene becomes evidence only through the accompanying account of what matters, why it matters and to whom. A common application can preserve the comparability of formats while flattening distinctions if context is stripped away. The article therefore reframes digital participation as an interpretative infrastructure rather than a machine for accumulating interchangeable urban photographs. It spans public health, participatory planning, media methods and translocal comparison. Its importance lies in treating comparability as a problem to be designed and negotiated rather than a property guaranteed by standardised software.
