I need your help in clarifying my understanding of the various states of an app. I am going to state my interpretation - but please feel free to correct me.
1) A
Apple documentation: UIApplicationState Constants Reference
.Active | Objective-C: UIApplicationStateActiveThe app is running in the foreground and currently receiving events.
Available in iOS 4.0 and later.
.Inactive | Objective-C: UIApplicationStateInactiveThe app is running in the foreground but is not receiving events. This might happen as a result of an interruption or because the app is transitioning to or from the background.
Available in iOS 4.0 and later.
.Background | Objective-C: UIApplicationStateBackgroundThe app is running in the background.
Available in iOS 4.0 and later.