Why would you think I was joking. At ease was a simplified interface from the regular finder. It’s primary change was to flatten the file hierarchy into a limited set of panels. It pre-dated both palm os and iOS, and informed the design of both of them.
Because there are files, folders, windows, and the entire suite. This resembles MS Bob (as the linked webpage says) more than it does resemble PalmOS / iOS.
Initial versions of PalmOS / iOS had no files whatsoever, at least visible to the user. If you had say a document editing app on iOS/PalmOS, and you uninstall it, your documents are absolutely gone from the device unless you backed them up somewhere else. The app "owns" the documents. On iOS, this is because apps can only access their private storage space with a few exceptions; on PalmOS this is because there is no filesystem whatsoever so all your apps can do is store stuff on your application's private database, also with a few exceptions (e.g., PalmDOC standard for ebooks). There are no folders, just "categories" or tags at most, there's no way to "browse files" because there aren't, just "apps" and a app launcher which you reach through a home button, and there's no way to share information between apps except through the clipboard.
This "at ease" is clearly showing a shared filesystem where apps can load/save random documents to, and in fact it even shows you can create folders and subfolders... http://toastytech.com/guis/ateasesubfolder.png
