In 2010, the computer truly went mobile.

Sure, users of Apple Inc.'s iPhone have had the Web in their hands since 2007. But this past year, smartphones plunged into the mainstream, giving millions of people the ability to browse the Internet, watch movies and stream music anywhere they could maintain a cellular or Wi-Fi connection -- and without having to find a place to sit down and boot up a laptop.

There were 81 million smartphones sold world-wide in the third quarter, the analysts at Gartner say, almost twice as many as a year earlier. They accounted for nearly one in five mobile phones sold that quarter. The chiefs of Verizon Communications Inc. and AT&T Inc. think smartphones could account for nearly three of every four phones sold by the middle of the decade.

This surge has upended the balance of power in the wireless market.

Devices running on Android, the software distributed by Google Inc., and Apple's iOS have shot past Research In Motion Ltd's BlackBerry, Gartner data show. Android is even closing in on market leader Nokia Corp., which has struggled and replaced its CEO this year.

Microsoft Corp., a powerhouse on the desktop, is struggling to find a foothold, with just 2.8% of the market for its mobile operating system in the third quarter. It has pinned its hopes on devices running a new version, Windows Phone 7, which are just hitting stores.

This past year also saw the tabletcomputer finally get traction, thanks to Apple and its iPad. The company sold 7.5 million iPads in their first six months on the market, and Gartner thinks nearly 55 million tablets will sell next year.

The momentum in technology is now with devices that can easily be carried around and the applications that sustain them.

The Journal runs through the defining moments of that transition this year and look at what to expect in 2011:

IPAD

Apple created a new mobile category with its iPad touchscreen tabletcomputer, which went on sale in early April. Despite the notable failures of companies like Microsoft to sell a tablet-like device in the past, Apple proved the combination of a sleek device, a high-resolution display and content via iTunes could appeal to consumers. Analysts at Citigroup estimate Apple will sell about 14 million iPads this year, and some analysts say it could have shipped even more if Apple's supply had kept up.

Coming next: Competition. So far, Apple has had the tablet market essentially to itself, with Samsung Electronics Co.'s Galaxy Tab its only real competitor. The New Year will bring alternatives from Motorola Inc. and RIM among others.

ANDROID

This year saw the iPhone gain its first worthycompetitors. And nearly all of them are powered by Google's mobile operating system, Android. While the first Android device was launched two years ago, it wasn't until 2010 that Android hit its stride. Credit Google's partnership with Verizon Wireless and two phone makers -- Motorola and HTC Corp. The collaboration produced a series of hit phones this year and saw Android pass Apple in market share.

Coming next: Cheap smartphones. Android's next move is downmarket, with some predicting Android phones will sell at unsubsidized prices under $100. That plus cheaper data plans could dramatically expand smartphone penetration.

APPS

2010 was the Year of the App. Sometimes cheap, often silly, these little computer programs -- there are hundreds of thousands of them -- turned smartphones into game rooms, barcode scanners and photo manipulators.

Three years after Apple reluctantly opened its iPhone to outside developers, apps have grown from time-killers into an ecosystem seen as a key to keeping consumers loyal to their phones. That explains why companies like Google, RIM and Verizon have jumped into the game and opened their own online marketplaces for third-party programs.

Apps, many of which cost just 99 cents each, have also spawned a cottage industry with thousands of developers, established software vendors and start-ups focused on churning out mobile programs. Gartner estimates that global app sales will total $6.7 billion in 2010. Look no further than Rovio Mobile's goofy 'Angry Bird' game, which has sold 12 million copies.

Coming next: Apps go corporate. AT&T, business-software developer SAP AG and other companies are working on apps that can help their employees track sales, monitorsystems or check-out customers without being tied to their stations.

GOING 4G

U.S. wireless networks moved solidly into their fourth generation this year, with Sprint launching the first 4G handsets this summer and Verizon Wireless rolling out its own 4G network this month. The first generation was analog. The second was digital, which made better use of spectrum and was more secure. The third allowed fast data connections. The fourth-generation technology promises super-fast broadband service that will make wireless video a breeze. For now, it's mainly a service for laptops, and nationwide coverage doesn't yet exist. But phones will be pouring out in the year ahead, and the networks are expanding. Now if the carriers would just agree on what qualifies. T-Mobile announced it has the nation's largest 4G network. Sprint and Verizon says it's just an advanced form of 3G.

Coming next: Paying for what you use. Carriers are looking to cash in as data use grows. AT&T has already dropped its unlimited data plan for new users. Verizon plans to adopt of some consumption pricing as it transitions to 4G. Users are going to have to start watching bits the way they used to count minutes.

PARTS SHORTAGES

Fancy smartphones were all the rage, but humble transistors, resistors and screens showed their clout this year. HTC's Droid Incredible went on prolonged back order almost immediately after its April launch due to shortages of its high-tech display. Insufficient supplies of basic components like semiconductors used in wireless base stations cost network-equipment company Ericsson around $500 million in sales in the second quarter. Shortages of networkequipment in turn held up AT&T's promised improvement of its much-criticized network in San Francisco.

Coming next: Samsung. The company's mobile-display business, which has had difficulty meeting demand for ultrathin screens for smartphones, is boosting production with a new facility that opens in July. Capacity will go up to 30 million screens a month from three million currently.

PATENT WARS