The citizens of Sofia can use the free mobile app on the platform of Sofia Municipality to submit signals. The application “Call Sofiа – Sofia Municipality Contact Center” is available to the users of Android and iOS devices through Google play и App Store, through the profiles in Google, Facebook, or through one-time registration. Due to the current situation a special section “COVID-19” is implemented for submitting signals on breaches of the anti-epidemic measures introduces at the territory of Sofia Municipality. A new function is added to the mobile version of the Contact Center, allowing to submit applications for voluntary work in the fight against COVID-19. The function is active through the Desktop application of the Contact Center.