Apple released iOS 13.7 on September 1, and as is traditional, Apple has now stopped signing iOS 13.6.1, making downgrading to that version of iOS no longer possible.
iOS 13.6.1 was released in August and fixed a known issue related to the Exposure Notifications and another bug that could make the displays exhibit a green tint.
iOS 13.7 was a major update that includes a new Exposure Notifications System that doesn’t require an app to be downloaded to turn the feature on.
Once they have updated their iPhone to iOS 13.7, users will see a new Exposure Notification section in the Settings app, which has been moved over from the Privacy settings. They’ll see a toggle to “Turn on Exposure Notifications.”
Once you’ve activated the feature, it lets you know if the feature is available in your country, state, or region via a contact tracing app. In areas that are participating in the Exposure Notifications Express program, users will be able to turn on Exposure Notifications without the need to download an app.
Apple is known to stop signing older versions of operating systems after it releases a public update, as part of an effort to encourage users to keep their devices’ operating systems up to date.