During a recent edition of TUAW TV Live, the question of how iCloud works in applications came up. After some internal consultation, we came to the conclusion that Apple has fully announced this feature and that its workings would not be considered confidential.
In that spirit, here's an introduction to iCloud's internals summarized from material in my upcoming iOS 5 Developer's Cookbook expanded edition.
In its simplest form, iCloud is merely a special folder. It lives on the iOS device in /private/var/mobile/Library/Mobile Documents/. That folder hosts all application material that applications share to the
