Apple released a new version of the free iPhone SDK which now includes Interface Builder.
Interface Builder is a tool for developers to visually create their user interface:
Apple released the first version of the iPhone SDK on March 6th.Interface Builder is Apple's graphical editor for designing user interface components for both Carbon and Cocoa applications. Interface Builder makes creating an application's user interface easier by allowing developers to use its graphical editing environment to manage virtually every aspect of creating a well designed user interface that adheres to the Aqua user interface guidelines.
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