Apple (s aapl), after announcing the sale of 450,000 iPads since Saturday, today unveiled its iPhone OS 4.0, the next evolution in the company’s mobile strategy. Although several of the new features, due for release this summer, were on my list of expectations two days ago, the bulk of them are indeed evolutionary — on the surface. But the implementation approach and polish of these new features are actually revolutionary because they don’t merely re-purpose the PC implementations of each task but are instead redesigned for mobile use. Here’s a rundown of what iPhone OS 4.0 devices will be capable of:
Multitasking — Apple has added seven APIs for developers to use in support of multitasking. Audio applications, VoIP programs and location-based services can all run in the background. And if a task isn’t complete when closing an app — say a photo upload — the task will continue until completion. Perhaps most clever is Apple’s re-use of the dock concept from OS X. Double-tapping the home button causes a dock-like tray to rise up on the screen so users can switch to another application. Multitasking and fast app switching will only be available for the iPhone 3GS, third-generation iPad touch and the iPad. “The hardware just can’t do it,” said Apple CEO Steve Jobs when referring to the first- and second-generation devices in his presentation today to developers and media in Cupertino, Calif.
Unified Inbox — The new inbox unifies multiple mail accounts into a single view, making it easier to navigate email. Attachments won’t be limited to QuickView, either — you can open mail items in supported third-party applications sold in the iTunes App Store. So a Microsoft Word (s msft) document, for example, could be instantly opened in a word processing program for editing purposes. Apple also lifted the limitation of one Microsoft Exchange account. That helps both enterprise and advanced power users with a hosted Exchange account or multiple Google (s GOOG) accounts. Speaking of Google, Apple adds a useful Google-like function with support for mail grouping by conversation.
iBooks — Apple’s new e-book platform debuted with the iPad, but will move to iPhone and iPod touch devices with this update. Taking a cue from Amazon (s amzn), iBooks will synchronize your place in a book when switching from one mobile Apple device to another.
Game Center — Now that there are 50,000 game titles for the iPhone platform, Apple is going to leverage them for a social gaming experience. Think Microsoft Xbox Live with achievements, multiplayer matchmaking and real-time leader boards. This feature was described as a “preview” in OS 4 that will be fully available later this year, although Apple wasn’t more specific on the time frame.
iAds — In another page from the Google playbook, Apple is entering the mobile advertising business. This makes sense, given the company’s purchase of Quattro in January. Developers using the interactive iAd platform –which leverages HTML5 — in their apps, will earn 60 percent of the revenue, with the rest going to Cupertino. Liz Gannes offers more perspective on Apple’s iAds from her on-site vantage point.
Folders and Wallpapers — In a very desktop-like paradigm, the new iPhone OS adds support for user-created folders and custom wallpapers. What’s the benefit of drag-and-drop folders? More apps. Instead of a limit of 180, folders can hold apps, raising the limit to 2,160 installable applications. Given how many apps we’re all installing — not to mention how much media we tote — it’s a safe bet that this summer will bring an iPhone with 64 GB of storage, just like the highest-priced iPad offers today.
Apple expects to release the new operating system to iPhone 3GS and third-generation iPod touches this summer, while the release for the iPad follows in the fall. The original iPhone, iPhone 3G and first two iPod touch iterations will be able to use some of the features, but not all. The new features should quell many critics of Apple’s mobile platform — it just gained the multitasking offered by other phones as well as several new features that make the iPad more of a notebook replacement. You’ll still be locked into Apple’s ecosystem, but that’s a price some are willing to pay for one company’s vision of mobile computing.