Prior to OS X Yosemite and Apple’s new iCloud Drive announced on Monday, Mac developers were explicitly required to succumb to the restraints of the Mac App Store to allow their customers to use iCloud file storage within their apps.
Now with the introduction of iCloud Drive, which gives users much clearer access to content stored in iCloud, developers can distribute their apps outside of the Mac App Store and trust that their users can opt to use iCloud for document storage as if they were sold in the Mac App Store…
iCloud Drive is already a big change in direction for Apple as it virtually tried to do away with the file system experience previously and silo files within apps, but this relatively lax approach to iCloud document storage is even more open in comparison.
For one, it gives developers one less reason to use the Mac App Store for distribution which applies the iOS model to desktop apps and in some cases introduce more complexities than it eliminates (see: Panic’s Coda 2.5).
This allows apps downloaded from the Web and other non-Mac App Store sources the same access to content stored in iCloud Drive as Mac App Store apps. For example, a Microsoft Word user on Mac user could access a document created in Pages on iOS and saved to iCloud Drive.
This change in policy was suspected as a result of Apple’s implementation of iCloud Drive within the OS X Finder, but Apple has clearly made the distinction that iCloud document storage will be available to all apps with Yosemite regardless of Mac App Store involvement.