These documents detail modifications, improvements, and known issues present in a pre-release version of Apple’s mobile operating system. They are essential for developers and advanced users testing the software prior to its general public availability. For example, such a document might outline changes to the user interface, security updates, or adjustments to application programming interfaces (APIs).
Accessing this information allows developers to prepare their applications for compatibility, identify potential bugs, and provide feedback to Apple. Historically, these notes have helped to ensure a smoother transition for users when the final version is eventually released. This proactive approach minimizes disruptions and enhances the overall user experience.