When Apple announced Lion and iOS the only mention of a cloud was the removal of tethering for iOS devices. Then, with the OS stuff out of the way they began to explain iCloud. The change, as Steve Jobs explained it, is that Apple no longer see your Mac/PC as the digital hub of your life: it’s now “the cloud” and that changes everything. The entire approach that Apple are now taking is more akin to Googles cloud strategy, but giving the end user the choice between web-apps, iOS apps or Mac apps to interact with their data.
Finally Apple have provided a system level API (that means developers can use it in their own apps) for document/file synchronising with the Cloud. This feature - this ONE feature alone is the single biggest annoucement Apple made at WWDC. To understand why it’s important to understand why document editing across multiple devices is so critical. As more people have A) more devices they use each day and B) collaborate and share documents in business, keeping documents in sync with each other is essential to avoid lost work and unnecessary frustration. At this time a handful of apps provide this functionality and it is mostly provided through Google Docs and through use of file storage services like DropBox. Now any developer, with any piece of software with settings or documents that work on more than one platform (iOS or OSX) can now access fully featured sync without a dollar spent all using Apples own maintained cloud storage solution.
The possibilities for iOS 5 applications is endless. Congratulations Apple for finally waking up, realising this is the future, and fingers crossed - for delivering it. Let’s not forget announcing products doesn’t equal flawless delivery. Expect teething problems, expect early frustration and then expect something amazing.