https://www.redmondpie.com/ios-10.3-and-apfs-why-you-may-want-to-backup-your-device-before-update/
iOS 10.3 And APFS: Why You May Want To Backup Your Device Before Update | Redmond Pie
Mar 25, 2017 - iOS 10.3 update will alter the way devices store files with the introduction of Apple File System, or APFS. Here's why you might want to backup your device...
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