Does anyone experiencing freezing during iPhone app launching or closing?

App freezes, and the device freezes sometime during la开发者_开发问答unching or closing. This happens especially to the app developed and installed using Xcode. Can anyone explain what's going on, if it's iOS 4 Gold Beta specific issue, or a generic task must be handled by a developer?

Use the Debugger, Console and NSLog() statements to track the progress of your application throughout its life. This will help you track the bug in your application.