The 2016­-2017 seismic sequence that struck the Central Italy severely damaging different towns, it showed how the marks of our culture can be deleted in an instant. The TECH4DA system (acronym of Technologies for Damage Assessment) was developed both to preserve the photographic memory and support the survey activities after a disaster. TECH4DA is a semi­-automatic system based on a client­-server architecture optimized for the Android and iOS mobile devices. The capability to store location and aspect of the buildings in different time allow to assess their changes due to an earthquake. TeCH4DA can be used by expert involved in damage assessment, although it has been designed for obtaining relevant contribution also from the citizens. The active and widespread participation of the citizens makes TECH4DA a platform based on the crowdsourcing. The Central Italy seismic sequence showed the difficulty to understand the cumulative effect due to a series of earthquakes occurred at short temporal distances. The capability to interrelate an image and a description to each event makes possible to freeze the damage progression at a specific date, enabling, a progressive and comparable analysis of the effects of an earthquake. TECH4DA is part of the products developed in the framework of the PON MASSIMO project aimed to the monitoring of the cultural heritage in seismic area [Montuori et al., 2016], which integrates non-­destructive and non-­invasive surveys based on satellite, airborne and terrestrial sensors. In this report, the technical development of the TECH4DA system is described, in addition to client server logic and the modules which compose the infrastructure. Moreover, some applications and potential future developments are outlined.