Cross-border data exchange between the Croatian Stop COVID-19 application and official applications of other EU member states has been established. This is the result of decisions and recommendations of the European Commission and the technical and safety requirements of the eHealth Network and other European bodies.

This makes Croatia the seventh EU country in a row, along with Denmark, Germany, Ireland, Italy, Latvia and Spain, which exchanges "infected keys" through the federation gateway (European Federation Gateway Service) and thus enables anonymous notification of foreign contacts about the risk of infection. COVID-19 disease.
 
By installing the application, including the setting for cross-border data exchange, you will ensure that you receive notification of exposure in the event of travel abroad or interaction with users of other authorized COVID-19 mobile applications in Croatia. Cross-border data exchange between national mobile contact tracking applications is defined by Commission Implementing Decision (EU) 2020/1023 of 15 July 2020.
 
The more people use the app, the more likely it is to have a positive effect on fighting the virus and the better we will be able to evaluate its effectiveness. Any successful notification means a potentially saved life. The takeover rate in the EU is currently between 1% and 38% of the population, depending on the Member State. But even with low use, it is possible to make a difference: researchers say that at 15% it can have a significant impact on spread and mortality. Therefore, everyone who has an application available is encouraged to install it and use it to inform others after a positive test result.