Delegation and Core Location - iOS Programming: The Big Nerd Ranch Guide - page 122

The essential build phases for creating an iOS application are Compile Sources , Link Bin-
ary With Libraries , and Copy Bundle Resources . We'll look at all three in detail at the end
of the chapter. For now, let's focus on Link Binary With Libraries and frameworks .
A framework is a collection of related classes that you can add to a target. Cocoa Touch is
a collection of frameworks. One of the benefits of Cocoa Touch being organized into
frameworks is that you only have to add the frameworks that a target needs.
To see what frameworks are already linked to your target, click the disclosure button next
to Link Binary With Libraries . Right now, there are three: the UIKit framework contains
classes that make up the iOS user interface, the Foundation framework includes classes
like NSString and NSArray , and Core Graphics enables the graphics library that we
will dig into starting in Chapter 6 .
Whereami also needs the Core Location framework, which includes the classes related to
finding a device's location. To add this framework to your target, click the plus (+) button
in the bottom left corner of the Link Binary With Libraries section. A sheet that displays
the available frameworks will appear ( Figure 4.3 ) . Select CoreLocation.framework
from this list and click Add .
Figure 4.3 Adding the Core Location framework