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    <p>While Daniel's answer is correct, I think it misses an important point. Namely:</p> <blockquote> <p>I find that using properties instead of plain old ivars just takes too much code and I don't really see the benefits if you're comfortable with memory management.</p> </blockquote> <p>The benefits are consistency; consistent memory management and consistent behavior.</p> <p>Notably, these two lines of code can actually have <em>extremely different</em> behavior at runtime:</p> <pre><code>iVar = [foo retain]; self.iVar = foo; </code></pre> <p>The first is a direct setting of the instance variable and there will be no change notifications. The second goes through the setter and, thus, preserves any subclass customizations upon set <em>and <strong>ensures that any observers of the property are notified of the change</em></strong>.</p> <p>If you are using ivars directly throughout your code (internally to the class -- if you are using ivars of an instance directly from <em>outside</em> that instance, well... any contractor working on your codebase should double their rates ;), then you must either also handle change notification propagation manually (typically by calling <code>willChangeValueForKey:</code>/<code>didChangeValueForKey</code>) <em>or</em> explicitly engineer your application to avoid use of mechanisms that rely upon Key-Value Observation.</p> <p>You say "takes too much code". I don't see that; in the above two lines of code, the dot syntax is fewer characters. Even calling the setter method using traditional syntax would be less code.</p> <p>And do not discount the value in centralizing memory management; one accidental omission in a myriad of call sites and crash city.</p>
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    1. POMust every ivar be a property?
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    1. COIn case people come here in the future and miss the surrounding comments, in iOS 4 you don't have to declare an ivar if you declare a property. This deals with a lot of the problems Diego discusses here.
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    2. COAnd with ARC in iOS 5 (and 4, with caveats), you also don't have to declare `dealloc`.
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    3. CO@bbum I'd be interested to get your feedback on a somewhat related question I asked, [Why would you use an ivar?](http://stackoverflow.com/q/9086736/590956)
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