Like PCs, mobile devices have many types of use -- which don't necessarily map to market share stats Android smartphones outsell iPhones 3:1 or 4:1 worldwide, depending on whose data you believe. But Android smartphones account for only a third of mobile Web traffic globally, and iPhones account for about a quarter. In the United States, iPhone sales are nearly even with Android sales, but the iPhone accounts for about two-thirds of smartphone Web traffic. For tablets, iPad Web usage also is much higher than its sales percentage would indicate.How to explain the contradiction between sales and persence on the Web? The answer is that a smartphone isn’t necessarily used as one. And neither are tablets.[ Bob Violino and Robert Scheier show how businesses today are successfully taking advantage of mobile tech, in InfoWorld’s Mobile Enablement Digital Spotlight PDF special report. | Keep up on key mobile developments and insights with the Mobilize newsletter. ] Apple’s iPhone and iPad are premium devices, as critics like to point out. The folks who buy them tend to really use them — we saw that phenomenon on Black Friday a few weeks back, where iOS devices comprised the bulk of mobile shopping. iOS users go to websites and interact them, and they use lots of apps, many of which involve Internet connectivity.The Android world, by contrast, is a mélange of levels, with devices ranging from $49 to $600 for both tablets and smartphones. People who buy the top-of-the-line Android smartphones, whose costs rival that of the iPhone, do as much on the Web and via apps as iPhone users, notes Carolina Milanesi, a mobile analyst at Gartner.But the bulk of the Android world is made up of users of cheaper devices, notes Ben Bajarain, an analyst at Creative Strategies. He points out that Android is more like the PC market in that it has high-end devices, everyday devices, low-cost devices, and super-low-cost devices. The different classes are used for different purposes, many of which don’t involve accessing the Web or even using the Internet. Plus, Chinese users — a lot of whom buy Android devices from local manufacturers — don’t show up nearly as much as counterparts elsewhere in the world due to China’s “great firewall” that limits their access to the non-Chinese Web. The explosion of sub-$150 tablets across the world is also a factor, Bajarin notes. Many of these devices, if not most, are used essentially as e-readers and virtual DVD players — Amazon’s Kindle line, for example. One segment is used for kids’ edutainment apps. Even when they use the Web to get apps or content, they’re not perusing the Web at large, so don’t tend to show up in Web-tracking studies, which typically are centered around websites that do ad-tracking to get their data.IDC’s tablet sales breakdown. The Others category at top is composed mainly of low-cost tablets plus Amazon’s Kindle Fire — the tablet world’s version of netbooks, which don’t show up much in Web usage surveys. You can see that the Others category has shrunk slightly since last year, likely due to people graduating to higher-end devices, especially in the Android world.Bajarin likens those devices to netboooks, a category of laptop that saw a few years of high growth, then got killed off by tablets. Netbooks had terrible performance, even though they were cheap, and quickly fell into disuse. I suspect many cheapo tablets have a similar trajectory as disposable, impulse buys. Others are relegated to offline uses, such as keeping kids from fighting on long car rides or providing entertainment for adults on a long flight, but otherwise sit idle.Such episodic use is not a criticism — my iPad Mini serves a similar role, though it can and is sometimes used to do much more — but an acknowldgement that just as PCs have many uses, so do mobile devices. However, we tend to think of them monolithically, likely because they are new. That makes sense to me. But one thing that doesn’t is the sizable discrepancy in Web usage between Android devices and iOS devices in the United States, relative to their market share. Given that a smartphone incurs a monthly extra cost of $40 to $60 — a small fortune for many people — for the privilege of data access, why on earth would people buy them, then not take regular advantage of that data connectivity?Bajarin thinks he knows why: People who tend to buy Android smartphones, and now Windows Phones (more popular in Europe than in the United States), are attracted by the cheaper prices and tend to be coming from regular cellphones. Thus, they’re not really clear what a smartphone can do for them, and they tend to use them like their old cellphones: to talk and text, plus do some social networking.But, Bajarin notes, such users tend to figure out that a smartphone is more than a cellphone with a touch screen, so they often trade up to a more capable model after their contract expires — and begin to take better advantage of what a smartphone can do. We early adopters tend to forget that it takes years for such revolutionary techbnology to get broad, meaningful adoption. That’s now happening. Still, there’ll be different levels of usage for smartphones, and moreso for tablets, just as there are for PCs 30-plus years after they debuted. Maybe we’ll devise a more meaningful classification system for mobile devices. Or maybe, as in the case of PCs, we’ll let price be that proxy and stop trying to equate usage with overall market share.This article, “When a smartphone is not a smartphone, and a tablet is not a tablet,” was originally published at InfoWorld.com. Read more of Galen Gruman’s Mobile Edge blog and follow the latest developments in mobile technology at InfoWorld.com. Follow Galen’s mobile musings on Twitter at MobileGalen. For the latest business technology news, follow InfoWorld.com on Twitter. Technology Industry