App Configuration
When creating an app, you will most likely need to store user preferences or other configuration data to customize or control the behavior of the application. While this can be done server-side, local configuration is faster. Apple provides NSUserDefaults to store small configuration items between the app and its extensions. These items must be PList serializable (NSData, NSString, NSNumber, NSDate, NSArray, & NSDictionary), but helper methods exist for serializing and deserializing primitives (as well as NSURL)....