The year 2011 was one in which smartphones and tablets achieved a status of necessity, instead of being style statement which they used to be in the past, thanks to Apple and Google.

Apple launched its iPad and iPhone 4 successors -- iPad 2 and iPhone 4S - and got an overwhelming response while Samsung unveiled Galaxy S2 and Galaxy Nexus, which is the first smartphone to run on Google's Ice Cream Sandwich (Android 4.0) operating system.

Features on Android 4.0 include widgets in a new tab, a customizable launcher, Gmail with offline search, a two-line preview and a new action bar at the bottom. It also has better voice integration, improved copy-and-paste functionality and a new tabbed Web browser that allows up to 16 tabs.

The year also saw online retail giant Amazon foraying into mobile computing arena with its Kindle Fire tablet.

Following are our top 10 gadgets that enthralled geeks in 2011: Apple iPhone 4S, Samsung Galaxy Nexus, Apple iPad 2, Samsung Galaxy S2, Samsung Galaxy Tab 10.1, Amazon Kindle Fire, Samsung Galaxy Note, MacBook Air 13, HTC Sensation XL and Motorola Droid Razr.

iPhone 4S

The latest smartphone from Apple, which was released on Oct. 4, a day before the death of Steve Jobs, has already become a cult with a new operating system in the form of iOS 5, iCloud and Siri voice assistant. iPhone 4S officially sold 4 million units during its opening weekend.

Despite missing prominent specifications like edge-to-edge design, a larger display, 4G LTE, and near-field communication (NFC) technology, iPhone 4S has some important features that were rumored to be part of the imaginary iPhone 5.

The features of the Apple smartphone include a 1GHz dual-core ARM Cortex-A9 processor, PowerVR SGX543MP2 GPU, Apple A5 chipset, and 8-megapixel camera capturing videos at 1080 pixels. It also has a 3.5-inch TFT Retina multitouch display, and is loaded with iOS 5. The device measures 115.2 x 58.6 x 9.3 mm and weighs 140 grams.

Samsung Galaxy Nexus

Google and Samsung unveiled Galaxy Nexus, the first smartphone running on Android 4.0 Ice Cream Sandwich, at an event in Hong Kong on Oct. 18.

The Galaxy Nexus -- measuring 135.5 x 67.94 x 8.94 mm, and weighing 135 grams -- is also known as Samsung Google Nexus Prime, Samsung Google Galaxy Nexus I9250, Samsung Google Nexus 3, and Samsung Google Nexus 4G.

The Galaxy Nexus sports a dual-core 1.2GHz Cortex-A9 CPU, TI OMAP 4460 chipset, 4.65-inch high-definition Super AMOLED display with about 316 ppi pixel density, 1GB of RAM, 16GB or 32GB of internal memory, NFC support, 5-megapixel rear-facing camera with 1080p video capture, and 1.3-megapixel front-facing camera for video calls.

The smartphone has an oleophobic surface, a multitouch input method, an accelerometer sensor for UI autorotate, touch-sensitive controls, a proximity sensor for auto turn-off, and a three-axis gyro sensor.

Apple iPad 2

iPad 2 is the second generation of the iPad. The tablet, which runs on iOS 5, is 15 percent lighter and 33 percent thinner than its predecessor. Apple unveiled the device on March 2, 2011, began selling it on its Web site and retail stores on March 11, and released it in 25 other countries on March 25, including Australia, Britain and Canada.

iPad 2, which weighs 601 grams, has a lithium-ion polymer battery that lasts up to 10 hours, a new 1GHz dual-core Apple A5 processor and VGA front-facing and 720p rear-facing cameras designed for FaceTime video calling. The device has 9.7 inches LED display with 1024x768 resolution at 132 pixels per inch (ppi).

iPad is one of the best-selling gadgets, and Apple recently announced it sold more than 25 million devices since the iPad was launched in April 2010. In 2011, iPad is expected to take 83 percent of the tablet computing market share in the United States.

Samsung Galaxy S2

Samsung Galaxy S2 received overwhelming responses from around the world. Galaxy S2, which runs on Android 2.3 Gingerbread OS and sports Samsung's TouchWiz UI, comes in three variants, on AT&T, T-Mobile and Sprint, whose version is called Samsung Galaxy S2 Epic. It has been officially known that Galaxy S2 would be upgradable to Google Inc.'s smartphone operating system.

The  AT&T version retains 4.3-inch display, featuring 125.3 x 66.1 x 8.5 mm dimension and weighs 116 grams. The smartphone is powered by a dual-core 1.2 GHz ARM Cortex-A9, Mali-400MP GPU Orion chipset.

Galaxy S2 also has an 8-megapixel camera with flash and can record HD video in 1080 pixels. The phone also has the front-facing 2-megapixel camera for video chat.

Samsung Galaxy Tab 10.1

Galaxy Tab 10.1 was first released in February but at that time Samsung showcased a rather bulkier frame measuring 10.92 mm thickness. After Apple launched its game-changing lighter and slimmer iPad 2, Samsung changed its Galaxy Tab 10.1 to an ultra-thin beauty flaunting an 8.6 mm thickness and weighing a mere 565 grams.

Samsung Galaxy Tab 10.1 features a 10.1-inch display with 1280x800 screen resolution and runs on Android Honeycomb operating system. It is powered by a dual-core 1GHz NVIDIA Tegra 2 chipset and offers 1GB RAM and comes in 16/32/64 GB internal memory configuration. It also features an 3MP rear-facing and 2MP front facing cameras. The tablet offers 1080p video playback support.

Amazon Kindle Fire

Amazon began shipping its Kindle Fire tablet on Nov.14. The product, which sells at $199, features a vibrant 7-inch color touch screen offering 1024x600 resolution with 169 ppi, a 1GHz dual-core processor, 512MB RAM and a new browser - Amazon Silk - as well as the Amazon Web Services cloud.

Kindle Fire is built on the older generation of Android systems (Android 2.2 Froyo) and lacks a camera, which may disappoint photo enthusiasts. 

However, Amazon has strong content to offset these shortcomings and it mainly targets customers who use tablets lightly and have a tight budget. The tablet is appealing to an entertainment hungry audience, as Amazon will integrate the tablet tightly with its Cloud services that sells books, movies and music, providing stiff competition to Apple in terms of content.

Samsung Galaxy Note

In September, Samsung unveiled its Galaxy Note with a huge 5.3-inch display, which is claimed to be the world's largest smartphone screen.

Galaxy Note is adorned with a 1.4GHz dual-core ARM Cortex-A9 processor, Mali-400MP GPU, Exynos chipset with 1 GB RAM, and 5.3-inch Super AMOLED high-definition display that has 1280-by-800-pixel resolution with 285 ppi pixel density.

In addition, the phone runs on Android 2.3 Gingerbread with the Samsung S Pen interface, which is said to bring a selection of applications designed specifically for the included stylus.

Samsung recently confirmed the smartphone/tablet hybrid would be upgradeable to Google's Android 4.0 Ice Cream Sandwich early next year.

Galaxy Note comes with 8-megapixel autofocus LED flash rear-facing camera with 1080p video capture and a 2-megapixel front-facing secondary camera for video chat. The smartphone, available with either 16GB or 32GB of internal storage and expandable up to 32GB via a microSD card, has a Gorilla Glass display and Samsung TouchWiz UI 4.0 version. The phone measures 146.9 x 83 x 9.7 mm, and weighs 178 grams.

MacBook Air 13

On July 20, 2011, Apple released an updated model of MacBook Air 13 in the same form factor as the prior model. The new model was powered by new dual-core Intel Core i5 and i7 processors, had a backlit keyboard, Thunderbolt instead of Mini DisplayPort and Bluetooth was upgraded to v4.0.

The notebook runs on Mac OS X Lion and sports a sleek thin aluminum frame, a full-sized keyboard and screen and no moving parts. MacBook Air's display offers a 1440x900 resolution, and is powered by 1.7 GHz dual-core Intel Core i5 to 1.8 GHz dual-core Intel Core i7. The notebook has 4GB RAM, with 128GB or 256GB flash storage.

HTC Sensation XL

HTC released its Sensation XL with Beats Audio in the UK market on Oct. 6. Despite not hitting the U.S. shores officially, the HTC Sensation XL with its huge 4.7-inch screen. The HTC smartphone is not expected to be offered from any of the carriers of United States, but consumers can get unlocked version of the phone and make it compatible with the AT&T network.

HTC Sensation XL, which runs on Google Inc.'s Android 2.3 Gingerbread OS, is adorned with 1.5 GHz Scorpion processor, Adreno 205 GPU, Qualcomm MSM8255 chipset, 4.7-inch S-LCD capacitive display, 768 MB of RAM, 16 GB of internal memory, 8-megapixel rear-facing dual-LED flash camera with 720p video capture and 1.3-megapixel front-facing camera for video calls.  The device measures 132.5 x 70.7 x 9.9 mm and weighs 162.5 grams.

Motorola Droid Razr

Motorola unveiled the Droid RAZR, claimed to be the world's thinnest smartphone with a mere 7.1 mm thickness, on Oct. 18. The Droid RAZR runs on the Android 2.3 Gingerbread OS.

The Droid RAZR is adorned with a 1.2 GHz dual-core Cortex-A9 CPU, PowerVR SGX540 GPU, TI OMAP 4430 chipset and 4.3-inch Super AMOLED display that has qHD resolution with pixel density of about 256 ppi. It comes with 1GB RAM and 16GB ROM.

It features WebTop interfaces like the Droid Bionic, Atrix, Photon, and others. Thus, to run the full Firefox browser, the user can tie it up to one of Motorola's lapdocks. The phone comes with 8-megapixel autofocus LED flash rear-facing camera with 1080p video capture and a 2-megapixel front-facing secondary camera for video chat.

The smartphone, with its 16GB of internal storage and 16GB microSD external card preinstalled (expandable up to 32GB), has a Gorilla Glass display, multitouch input method, accelerometer sensor for UI autorotate, and proximity sensor for auto turn-off. The phone measures 130.7 x 68.9 x 7.1 mm, and weighs 127 grams.