<p>Coastal protection structures such as seawalls and groins play a critical role in mitigating coastal erosion and flood risks, yet large-scale, field-based assessments of their condition remain limited due to methodological, logistical, and cost-related constraints. This study presents a mobile GIS framework for the in-situ measurement and classification of coastal defence infrastructure using a web-application developed on Kobo Toolbox, an open-source platform configured to support standardized, georeferenced, and multimedia-enabled data collection in remote or resource-constrained environments. The framework was piloted along Kerala’s 593-kilometre coastline in India, a geomorphologically diverse region characterised by seasonal erosion and high exposure to climate-related hazards. Field deployment during the monsoon season resulted in 1,420 structured survey records of coastal features, supported by over 3,500 handheld GPS observations and approximately 20 gigabytes of photographic documentation collected by trained survey teams. Structures were classified as intact, partially damaged, or totally disintegrated, with condition assessments linked to functional performance metrics such as beach width and sediment deposition patterns. Collected data were centrally managed, validated through expert review, and integrated into GIS environments for spatial analysis and reporting. A qualitative comparison with traditional field surveys, UAV photogrammetry, satellite remote sensing, and citizen-science-based monitoring highlights the framework’s strengths in data consistency, scalability, operation efficiency, and suitability for routine deployment. Designed for use by non-specialist field teams, the proposed framework provides a replicable and cost-effective solution for structured coastal infrastructure monitoring and supports institutional capacity building for long-term shoreline management.</p>