Reading Files belonging to other Apps iOS

I am currently coding a backup app for iOS, and I want to have options to let the user back up things like Application Data (other app's documents, etc,) Contacts, Safari Bookmarks, and all that fun stuff.

I'd开发者_JAVA技巧 like to know if that's possible, how I'd do it, and where those files are stored, and most importantly, if this is actually allowed by Apple. I read through their docs, and I haven't seen anything that speaks against it.

It's not possible. Your app isn't even capable of reading the documents from other apps. This is accomplished via sandboxing. Every read/write your application tries to do to the filesystem is checked by the kernel to ensure you're staying within your sandbox. The documents belonging to other apps are outside of your sandbox, so you cannot see them.

They aren't allowed. All iOS apps are sandboxed, and can't access other apps' data.

Your app, naturally is in a sandbox, which does not allow you to read outside of the app. If you jailbreak your device, then yes, it is possible.