The Internet has two faces

NEW YORK (Fortune) -- Not that long ago, most Americans had a hard time imagining using their mobile phones to connect to the Internet. Even users of early smartphones such as the first BlackBerry devices found the process slow and tough to navigate. And for users of traditional phones with nothing but numeric keypads, Web surfing on a cell was just plain painful, not to mention expensive.

That, of course, was before the iPhone (and the proliferation of broadband 3G wireless networks), which transformed the mobile Internet experience with a vastly superior user interface, speedier access and, more recently, a cornucopia of downloadable applications ("apps" in tech parlance) that can turn the phone into everything from a mobile office to a walking videogame arcade.

iPhone users aren't the only ones using the mobile Web. In January, more than 22 million Americans used their cell phones to surf the Internet - more than double the number from a year ago, according to comScore. Smart phones are taking off, increasing sales even as the overall cell phone market begins to slide. The network is also becoming faster and more widely available every day.

Indeed, the long-anticipated idea of an ubiquitous Web - one people access anywhere they are - is finally becoming a reality. Does this mean that we'll soon be trading in our PCs in the same way many of us gave up our landlines in favor of our cell phones?

At first blush it may seem that the wired Web is actually ceding ground to its mobile cousin: Apple's (AAPL, Fortune 500) App Store has paved the way for application storefronts from Blackberry, and Google's (GOOG, Fortune 500) Android; Microsoft (MSFT, Fortune 500), Nokia (NOK) and Palm each plan to launch stores in the coming months.

In some cases these apps utilize the device's native features - the accelerometer, its location awareness - making them uniquely applicable to the mobile environment, as with games and maps. In other cases they are no more than an app wrapped around a Web site, offering direct access and a superb user experience. The apps are also available through online "stores" - though many are free - making them easier to find.

And while many apps have transformed the Web, they also can be costly to deploy. First they require specialized programming skills to create, and experts claim there aren't enough developers with these skills to meet the growing needs of the industry. Second, it is extremely challenging to design a product with a user interface that can run across different devices with different operating systems and carrier networks.

Meanwhile, Web browsers - the main tool most consumers use to utilize the Web (in wired or unwired settings) remain less usable on the go than at a laptop or desktop. Web sites designed for a full-screen, wired experience (meaning a broadband connection) don't translate easily to mobile devices due to limitations of processing speed, the network, and screen size. Heavy images and flash technology tend to trip things up. This is complicated by the fact that mobile users tend to have a limited attention span compared to when they are sitting in front of a computer. But the ability to access the same site from any device offers a huge advantage over an app. Not only is a Web site easier and cheaper to code, it's unnecessary to redesign it for every new device that comes along.

So what will it take to bring the mobile Web to life in a way that is both sustainable and suited to the mobile experience? And what are the consequences for apps and for the wired Web?

To start, we have to stop thinking about cell phones and Blackberrys as devices for making calls and sending e-mail. Mobile devices are our personal keys to access the Web all around us. The Web is everywhere, but we tend to access it two ways - from a fixed, wired location or on a cellular network from wherever we happen to be (laptops and more so, netbooks, occupy a middle ground). The benefits of one context are quite often the limitations of the other, and these attributes often complement the different needs we have of them.

For example, in a wired setting we enjoy sites with full features, content and graphics, thanks to a big screen, high processing power and large bandwidth. We don't have these benefits with our mobile devices, but we usually don't need them. Instead, mobile Web sites should offer us the basic information we are most likely seeking - the same functionality and information many of the apps currently offer.

In the case of a bank, this could be the ability to review accounts, transfer funds and pay bills. An airline site might enable users to check flight status or do a quick fare search. A restaurant should prominently display its phone number, with the option to click to call, and its address, linked to a map showing that location in relation to the user's. The sites are dumbed-down in a way that takes advantage of the smart capabilities of the device.

Industry backed consortiums like dotMobi are helping facilitate the growth of the mobile Web by spearheading standardization and creating tools that translate Web site content into a user-friendly mobile site. DotMobi is also making it easier to find mobile Web sites, with naming protocols like its ".mobi" domain.

The number of mobile-friendly sites has grown seven-fold in the past year, from 150,000 to about 1.1 million. In emerging countries, where mobile phones are much more prevalent than computers, the mobile Internet has surpassed the wired Web by default.

But this doesn't spell the overall demise of the wired Web, which will always be preferred in contexts that demand its unique capabilities, designing products, say, or even, for some consumers, reading documents. Nor will apps fade away as their predecessors, desktop widgets, have done. It has been said that there are sites that we live in and sites that we visit. The sites that we live in are the ones we are mostly like to have apps for - like the shortcuts on a computer desktop. The others will be sites that we visit via the mobile Web.

Then of course there are the fart-machine and virtual beer apps - works of genius that some might say eclipse anything the Internet has to offer.