[Someone]

I do not know what Steve said, but the way you state it, "app files" could be the files in the application itself, not user files made by an app. For performance and robustness, they will have more, but they need only one copy of those on their servers, and it could be the one in the App Store. The costs of storing those are a) peanuts, if you are Apple, and b) possibly recouped by the $99 developer fee.

[rsuttongee]

You're probably right that "app files" they way steve mentioned is does refer to the data of the apps themselves which isn't a lot of data.

I was more curious about data files that are used by an app (I'm assuming we can use the iCloud API to synch those between devices) - how is that paid for? does that count towards the 5GB limit? If so, can you get more space? at what cost?

For example, right now GoodReader uses the dropbox API to allow cloud access to whatever documents you have, and I have several gigs of various .pdfs that I store there. With the iCloud API, can Goodreader abandon dropbox and let apple host them?