iPad's new document sharing model
With the iPad, Apple demonstrated new multitouch versions of desktop-class iWorks apps with user interfaces that need to open and save documents. There's still no file system browser with open and save panels. Instead, each app displays the files it knows about at launch for the user to navigate through directly.
An iPad developer has revealed to AppleInsider how this new mechanism works, without also requiring that users learn about the complexity of the underlying file system. Rather than iPad apps saving their documents into a wide open file system, apps on iPad save all their documents within their own installation directory. Delete the app and you'll clean out all of its related files. This is how the iPhone OS already works.
Additionally, iPad apps can now specify that their documents be shared wirelessly. With that configuration, the iPad will make available each apps' documents, allowing the user to wirelessly mount their iPad via WiFi and simply drag and drop files back and forth between it and their desktop computer.
On the desktop system, the iPad will show up as a share containing a documents folder for each app that enables sharing. For example, a user with iWork apps will be able to wirelessly connect to their iPad as if it were a directly connected drive, and simply drag spreadsheet, presentation, or word processing files between their local system and the mobile device as desired.
Documents copied to the app's shared folder will be graphically presented by the app when it launches, sparing users from having to figure out where to look for their document files and avoiding any need to sort through different kinds of documents. The document listing also presents each file as a large preview akin to Quick View on the Mac OS X desktop.
And iPad app's documents can be presented in any way that makes sense, depending on how many and what kind of documents the individual iPad app uses. Apple demonstrated its Work apps scrolling through a quick list of documents, while its iBooks app presents its various digital books as titles in a virtual bookshelf.