Apple in the third iOS 13.5 beta introduced support for the Exposure Notification API it's developing with Google along with a toggle to enable it, and in the fourth beta of iOS 13.5 introduced today, Apple has tweaked the interface to make it more clear how exposure notification logging works.
In this beta, when accessing the Exposure Notification toggle located in the Health section of the Privacy part of the Settings app, Apple now makes it clear that the exposure notification logging feature can't be turned out without an accompanying app installed.
In a country where exposure notification is available, the new Exposure Logging toggle is grayed out and cannot be activated without an authorized app installed, as seen in the screenshot above.
You cannot turn on Exposure Logging without an authorized app installed that can send Exposure Notifications.
When enabled iPhone can exchange random IDs with other devices using Bluetooth.
The random IDs your device collects are stored in an exposure log for 14 days. This exposure log allows an app you authorize to notify you if you may have been exposed to COVID-19.
If you are diagnosed with COVID-19 you can choose to share your own device's random IDs with the authorized app so it can notify others anonymously.
In a country where there are no apps that take advantage of Exposure Notification, there's different wording letting you know the feature is not available and no toggle to turn on at all.
Beta users in the United States and other countries will see the warning about Exposure Notification not being available in the country as of yet because there are no apps that take advantage of Exposure Notification that can be downloaded at this time.
When health apps that use the Exposure Notification API are released, the Privacy section of the Settings app will also list the active Exposure Notification app that's installed.
