This study entitled analysis of functions and applications of siaran mobile (reporting and assignment application system) as a communication facility of South Tangerang City towards smart city. The purpose of this study was to analyze the functions and benefits of the SIARAN Mobile application as a facility of public communication in supporting South Tangerang City towards smart city. Supporting concepts and theories in this research were communication, public relations government, and smart city. This research method was to use a descriptive qualitative approach. The findings showed that the SIARAN Mobile application was a South Tangerang City reporting media based on the mobile application that was officially launched by the government since March 9^th, 2017. The function of this application was to become a reporting application for technical problems such as waste problems, damaged public facilities, actions which was detrimental to the community. The benefit of this application was to make it easier for the public to report various problems in the South Tangerang area, and make it easier for the government in handling various problems that were complained of by the community.