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Brief content (developer-related features):
iOS 6.0
Maps
In addition to the new map tiles provided by Apple, the Maps app and MapKit framework now support additional interactions with other apps.
Social Framework
The Social framework (Social.framework) provides a simple interface for accessing the user’s social media accounts.
Pass Kit
Pass Kit is a new technology that uses web services, a new file format, and an Objective-C framework (PassKit.framework) to implement support for downloadable passes.
Game Center
Game Center has been updated and new features have been added to improve the game playing experience.
Reminders
The Event Kit framework now includes interfaces for creating and accessing reminders on the user’s device.
In-App Purchase
The Store Kit framework (StoreKit.framework) now supports the purchasing of iTunes content inside your app and provides support for having downloadable content hosted on Apple servers
Collection Views
The UICollectionView class offers a new way to present ordered data to users. With a collection view object, you are now able to define the presentation and arrangement of embedded views
UI State Preservation
State preservation makes it easier for apps to restore their user interface to the state it was in when the user last used it.
Auto Layout
Auto layout improves upon the “springs and struts” model previously used to lay out the elements of a user interface. With auto layout, you define rules for how to lay out the elements in your user interface.
Data Privacy
In addition to location data, the system now asks the user’s permission before allowing third-party apps to access certain user data
Additional Framework Enhancements