Progress in Developing iOS and Cocoa
Blocks, Literals, ARC and more have been added to Cocoa helping to ease many of the pains developers experienced in the past. It is an awesome time to be an iOS or Mac developer.
Kevin Sylvestre
#mac (2 articles)
Extending Objects in Cocoa with Categories‎
Adding in functionality to an existing class in Cocoa is easy using categories. This can be useful for methods that should be transient or when access to the original code is restricted.