iPhone 5s iOS 12.5.1 Update: What's New
iOS 12.5.1 brings a bug fix for COVID-19 exposure notifications:
The previous version of iOS 12 brought support for COVID-19 exposure notifications.
iOS 12.5.1/iOS 12.5 let you opt-in to the COVID-19 Exposure Notifications system for your iPhone. System availability depends on support from your local public health authority.
iOS 12.5 also included one security patch which you can read about on Apple's security website.
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