1.

Use Foundation to:

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  Create and manage collections such as arrays and dictionaries.

  
  


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  Access images and other resources stored in your app.

  
  


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  Create and manage strings.

  
  


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  Post and observe notifications.

  
  


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  Create date and time objects.

  
  


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  Automatically discover devices on IP networks.

  
  


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  Manipulate URL streams.

  
  


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  Perform code asynchronously.

  
  

2.

Use UIKit to:

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  Construct and manage your user interface.

  
  


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  Handle touch and motion-based events.

  
  


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  Present text and web content.

  
  


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  Optimize your app for multitasking.

  
  


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  Create custom user-interface elements.

  
  

3.

Use Core Data to:

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  Save and retrieve objects from storage.

  
  


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  Support basic undo/redo.

  
  


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  Validate property values automatically.

  
  


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  Filter, group, and organize data in memory.

  
  


• 
  

  Manage results in a table view with [NSFetchedResultsController].

  
  


• 
  

  Support document-based applications

  
  

   

  
  

Survey the Major Frameworks:

1.iOS Apps Are Based on the Foundation and UIKit Frameworks.

2.Other Important Frameworks You Should Know About.

3.Add Other Frameworks to Your Project as Needed.