https://arstechnica.com/gadgets/2020/05/covid-19-contact-tracing-hits-apple-devices-with-ios-and-ipados-13-5/

Apple released iOS 13.5 and iPadOS 13.5 for iPhones, iPods, and iPads today. They went live alongside minor software updates for Apple TV and HomePod devices. The iOS update mainly adds new health-related features—most notably the much-discussed Exposure Notification API that was co-developed with Google to help local, regional, and national governments enact contact-tracing strategies to battle the COVID-19 pandemic.

Usage of the contact tracing API is user-optional. Additionally, exposure reports require the user to, once again, opt in to the notification, and it can only be done after the positive result is confirmed by one of the government agencies.