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Inside iCloud: Apple's new web services for iOS and Mac OS X Lion

Apple's iCloud services, announced this summer at the company's Worldwide Developer Conference, are quickly maturing for their initial release this fall. Here's what's new and what's changed.

Speaking at WWDC, Apple's chief executive Steve Jobs presented iCloud as three groups of online services that would be provided to iOS and Mac OS X Lion users in a composite package under the new brand name, replacing most of the company's existing MobileMe services.

The package is referred to as various "cloud" services because they are hosted on remote servers and available to desktop or mobile clients anywhere on the Internet through its nebulous cloud of network routers.

iCloud combines an improved group of messaging-related services originating in the existing MobileMe (including Mail, Contacts, Calendar) with a greatly expanded set of document and media-related services (including Photo Stream and Documents & Data), as well as an entirely new iCloud backup and new "iTunes in the Cloud" services to keep content (from music and video to apps and iBooks) wirelessly up to date across a user's devices.

A host of improvements over MobileMe

The first segment of iCloud services are essentially the next generation of Apple's existing MobileMe web apps. The company has enhanced its MobileMe web apps for Mail, Contacts and Calendars, unifying their look with the company's native iPad apps.

Besides the new look consistent with iPad (and Mac OS X Lion) apps, the other obviously discernible difference in iCloud's online Mail, Contacts and Calendar clients is a lot more speed. Working within the apps is simply much faster.

That may be due to the fact that nobody is using iCloud yet apart from Apple's developers testing the new system, but Apple has also greatly expanded its server-side capacity with the introduction of its new data center in North Carolina in addition to newly leased space in Silicon Valley.

One of the core advantages to cloud computing in general is that the vendor can flexibly allocate new server hardware to handle demand from users. This wasn't done exceptionally well for MobileMe, which is fairly slow in the US and painfully lethargic in many other countries.

However, it appears Apple has learned a lot since, and the deployment of its massive new server in North Carolina (along with other leased data center locations) will go a long way to backing up the intention of delivering a service that can sustain better performance. It's still not clear whether such a centralized service will work well for users outside the US, without some kind of help from CDN providers or local outposts of Apple run server locations. With more and more of Apple's business occurring outside the US, this will be an increasingly important issue.

The performance of iCloud's web apps is a combination of server capacity (now greatly enhanced), server-side software sophistication (which keeps improving, as noted below), network speed and latency (which Apple can't control for clients) and client side browser sophistication (which similarly keeps improving, allowing HTML5-style apps to increasingly improve in responsiveness, in part by leveraging hardware acceleration and improved JavaScript execution).

On page 2 of 3: What's new in iCloud's web apps.

What's new in iCloud's web apps

All of these factors are advancing in concert, making it no surprise that iCloud's web apps are a marked improvement over the previous generation of MobileMe. One new big leap for iCloud's web apps is that they're now officially HTML5.

While MobileMe apps were primarily served up as "XHTML 1.0 Strict," with some HTML5-associated features, iCloud apps are now straight-up HTML5, with its simple DOCTYPE of "html". While everyone is making efforts to support HTML5 in their browsers, that doesn't necessarily mean that iCloud will "just work" everywhere, just yet. Navigate to the site on your mobile device (including an iPhone or iPad), for example, and you still get a message to "visit on a Mac or PC for the Web Apps."

iCloud's web apps make use of Local Storage, which can, for example, keep a copy of calendar data stored on the client side, allowing the Calendar app to open and operate faster, as long as you're working on a machine where it makes sense to save a local copy (you might not want to copy your data to a shared, public terminal, for example).

iCloud also uses cookies of course, something that the site cutely reminds you of if you attempt to access it with cookies turned off in your browser

Expanded web apps

In addition to better, faster versions of its existing web apps, Apple is also expanding what services are available within its web apps. Apple seemingly took forever to add Notes sync to MobileMe in Mac OS X and iOS, and is just now preparing to add Reminders (aka To Dos) sync across the board, with a dedicated Reminders app in iOS 5 and prominent positioning of Notes within Lion Mail and Reminders in the Lion Calendar app.

iCloud continues to sync Safari bookmarks, although there is no longer a web interface for accessing them; presumably, if you use bookmark sync, you'll access them via the browser you use, rather than on a web page itself.

Apple also rewrote its Find My Phone web app for iCloud, which now incorporates support for finding Mac OS X Lion Macs connected to the same iCloud account as well. In addition to locating devices, the service can remotely lock or wipe a configured Mac.

There is also a new iWork component in the iCloud web apps, which allows users to see and download (in iWork, Office or PDF formats) any of the documents they've stored in the cloud using native iWork apps on either the Mac or iOS. This functionality, related to iCloud's new Documents & Data feature, will be examined more closely in the following segment.

On page 3 of 3: Banished components of MobileMe, Beyond web aps.

Banished components of MobileMe

There are also two missing components that are currently included in MobileMe: iDisk and Gallery. Rather than providing simple cloud storage for photos and documents like MobileMe, iCloud offers a far more sophisticated type of cloud storage, complete with version management and push updating across the devices you use.

Rather than being a "virtual disk in the cloud" like Dropbox or the former iDisk, there's now no need for users to manually copy documents to iCloud, manage those documents between devices, or think about how to retrieve those documents from their computers or mobile devices. iCloud taps into both iOS 5 and Mac OS X Lion at the system level, turning iCloud into a core operating system feature that just happens to be hosted by Apple rather than running locally on the machine.

Also missing from MobileMe is the entire concept of web hosting. Apple initially sold its .Mac service as an assortment of email and web hosting features, but relatively few saw the value in having Apple host their content; for users with serious needs for web hosting, Apple's offerings were too little, while casual users rarely had enough need for web hosting to make figuring out how to use .Mac worth their while.

With the transition to MobileMe, Apple downplayed its web hosting services and focused on push messaging, aiming directly at mobile users. This proved to be more popular and valuable to Apple's customers. The move to iCloud just moves further in that direction, erasing web hosting entirely along with the little used iWeb app for Mac OS X, and instead delivering personal document management tools that will be more valuable to most Mac and iOS users.

The result is that iCloud's services are now free rather than $99 per year, with users only needing to pay if they use more than 5GB of storage. The downside is that a few MobileMe users will need to find alternative web hosting services. Fortunately, they are plenty of free or inexpensive web and cloud storage services available to fill the void Apple is leaving behind.

Apple's MobileMe iDisk features were so little used that various features, such as its ability to stream background music playback, were not discovered by the mainstream media until nearly a month after they were released, and services offering similar features, such as Google Music, are still commonly believed to be unmatched by Apple by many tech pundits.

Beyond web apps

It's important to keep in mind that iCloud itself goes beyond just being a suite of web apps; just like MobileMe before it, iCloud is integrated right into the operating system as a core service on both iOS 5 and Mac OS X Lion.

Developers have expanded opportunities for integrating the new service into their own apps, and Apple has taken the lead in weaving its iCloud services deep into iPhoto, iTunes, iWork, messaging apps, and even core OS features such as Mac OS X's "Back to My Mac," which provides a secure way to discover and reach network sharing services on your home machine remotely across the Internet.

The next segment looking at iCloud will examine how Apple is serving up its a new generation of cloud storage and document sync features that extend beyond the web apps, basic push messaging and content sync features of today's MobileMe.