iCloud is an impressive web application. It’s an OS-like desktop, complete with storage space and a Microsoft Office-like application suite, that runs in a browser that you can access from anywhere. It’s a very slick-looking app and functions very well. Applications run snappily, and everything operates as you would expect based on using your desktop OS.

According to Xcerion, iCloud’s primary market is Internet cafe users, but with this release the company has introduced some interesting collaboration features that could be useful for web workers, particularly if you find yourself using more than one machine. You can share calendars and to-do items with teammates and, thanks to built-in social networking features, see when your colleagues are online and chat with them. Most impressive is the ability to simultaneously collaborate on a single shared document, with multiple people making edits.

iCloud’s XML backend is clever, and because the applications execute locally on your machine rather than on a remote server, they appear much more responsive than other “web OS” offerings that we’ve seen before.

Xcerion envisions a future in which you can access your iCloud desktop from anywhere, including mobile devices. The idea of completely virtualized applications  is very appealing:  I would love to be able to leave my documents, web pages, etc. open on a virtual desktop and be able to return to them later from any device, anywhere. Unfortunately, though, that vision doesn’t match the current reality.

Disappointingly, iCloud is only completely supported in Internet Explorer. Firefox support is in “early alpha” and works OK in my tests, but the company says that you shouldn’t rely on it, and as of yet, other browsers are totally unsupported. For that reason I (and I suspect many of you) won’t be taking up iCloud just yet.

What do you think of the idea of a “web OS”?

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XIOS/3 has many of the properties of an operating system (though strictly speaking it is more of a Web-hosted environment), and is targeted at online application development, collaboration, and sharing of free applications. It is XML-based, and uses AJAX to connect to back-end servers. If application developers begin to collaborate using it, it could become a promising new open-source platform and a flexible way for web workers to get jobs done.

XIOS/3’s desktop looks very much like the desktop that a Windows user is familiar with, complete with a sidebar on the right that resembles Google Sidebar (a clock, a weather widget, etc.), and tabs along the left that take you to programs you can run in the environment, a search engine, an XML editor for working with applications, and more.

Xcerion is backed financially by former Microsoft executives, and reports have already surfaced that XIOS/3 may begin to compete with Google and Microsoft in delivering numerous types of Web applications and services. For the time being, I see it as more of a Web 2.0 service that allows for collaboration on sophisticated online applications and sharing of those applications. It’s also in a limited beta version right now, so you need to apply to test the beta.

XIOS/3 allows you to do work offline and then automatically synch the work up with your data and applications when you go online. If I open up, say, a simple cash flow application and start changing values in the underlying data, then I go open another browser, my changes to the data will be reflected in the view in the second browser. In this way, web workers could easily collaborate on transaction-based, database-centric applications.

XIOS/3 also allows you to save data on your own hard drives, if you wish, or it can be stored online. Also, applications execute locally, so XIOS/3 is faster to use than some of the other Internet-based operating system offerings. It also has a very clean and easy XML editor.

To a large extent, the success of XIOS/3 will depend on coders building and sharing applications with it—just as standard operating systems have always depended on developers for success. You can find many screenshots of XIOS/3 and forthcoming applications at Xcerion’s home page. There is also a video demo and other information at the company’s blog.

The business model is to offer XIOS/3 and applications for it for free. In my own use, I found it stable, intuitive and good for collaborative application development. But what Excerion absolutely needs next, as is true in the Linux world and throughout the open-source arena, is enthusiastic developers.

Would you consider using a collaborative, browser-based spin on an operating system? Have you used any of the other Web-based OS offerings?

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