Xcode 5 Start to Finish: iOS and OS X Development

Precompilation

Mac and iOS applications draw on frameworks, packages of dynamic libraries, headers, and resources that define and link to the operating systems, human interface services, and other services. Frameworks entail huge numbers of large header files. In early days, it made sense for programmers to speed up builds by carefully choosing the system headers they included, but the Cocoa frameworks are so interdependent that that isn’t possible. (In fact, Apple emphatically warns against trying to pull pieces out of frameworks.)

Prefix Headers

Framework headers are usually the first things an implementation file imports, either directly or through headers of its own. You can set a prefix file to be injected automatically into the source ...