1. The term tablet PC may refer to: Tablet computer, a kind of mobile computer, usually having a touchscreen or pen-enabled interface A tablet personal computer, a class of tablet which runs an adapted version of a desktop operating system Microsoft Tablet PC, a class of Microsoft Windows-based tablets TABLET PC: A tablet computer, or simply tablet, is a one-piece, mobile version of a personal computer, primarily operated by touchscreen (the users finger essentially functions as the mouse and cursor, removing the need for the physical [i.e., mouse & keyboard] hardware components necessary for a desktop or laptop computer; and, an onscreen, hideable virtual keyboard is integrated into the display). Available in a variety of sizes, even the smallests touchscreens are much larger than those of a smart phone or personal digital  assistant. A tablet computer may be connected to a keyboard with a wireless link or a USB port. Convertible notebook computers have an integrated keyboard that can be hidden by a swivel joint or slidejoint, exposing only the screen for touch operation. Hybrids have a detachable keyboard so that the touch screen can be used as a stand-alone tablet.Booklets include dual-touchscreens, and can be used as a notebook by displaying a virtual keyboard in one of them. Alan Kays Dynabook described an information tablet in 1972: "A Personal Computer for  children of all Ages". The paper proposes a touch screen as a possible alternative means of input for the device. The first commercial portable electronic tablets appeared at the end of the 20th century. In 2010,Apple Inc. released the iPad which became the first mobile computer tablet to achieve worldwide commercial success. The iPad used technology similar to Apples iPhone. Other manufacturers have produced tablets of their own including Samsung, HTC, Motorola, RIM, Sony, Amazon, HP, Microsoft, Google, Asus, Toshiba, and Archos. Tablets use a variety of operating systems such as iOS (Apple), Android (Google), Windows (Microsoft), and QNX (RIM). As of March 2012, 31% of U.S. Internet users were reported to have a tablet, which was used  mainly for viewing published content such as video and news. Among tablets available in the market in 2012, the top-selling device is Apples iPad with 100 million sold by mid October  2012 since it was released in April 3, 2010, followed by Amazons Kindle Fire with 7 million,  and Barnes & Nobles Nook with 5 million.
3. 1888 telautograph patent schemaMain article: History of tablet computersThe tablet computer and the associated special operating software is an example of pencomputing technology, and thus the development of tablets has deep historical roots.Electrical devices with data input and output on a flat information display have existed as early as 1888 with the telautograph. Throughout the 20th century many devices with these characteristicshave been imagined and created whether as blueprints, prototypes, or commercial products. Inaddition to many academic and research systems, there were several companies with commercialproducts in the 1980s.Tablet computers appeared in a number of works of Science Fiction in the second half of the 20th century, with the depiction of Arthur C. ClarkesNewsPad, in Stanley Kubricks 1968 film 2001: ASpace Odyssey, the description of Calculator Pad in the 1951 novel Foundation by Isaac Asimov,the Opton in the 1961 novel Return from the Stars by Stanislaw Lem, The Hitchhikers Guide to theGalaxy in Douglas Adams 1978 comedy of the same name, and the numerous devices depicted inGene Roddenberry 1966 Star Trek series, all helping to promote and disseminate the concept to a wider audience.Alan Kay attempted to formulate his Dynabook portable computer concept as early as 1968; with his1972 paper: "A personal computer for children of all ages" detailing possible uses and functionality for his Dynabook concept.The sci-fi TV series Star Trek The Next Generation featured tablet computers which were designated as "padds".In 1994 the European Union initiated the OMI-NewsPAD project (EP9252), requiring a consumerdevice be developed for the receipt and consumption of electronically delivered news / newspapersand associated multi-media. The NewsPad name and project goals were borrowed from and inspiredby Arthur C. Clarkes 1965 screen play and Stanley Kubricks 1968 film 2001: A Space Odyssey. Acorn Computers developed and delivered an ARM based touch screen tablet computerfor this program, branded the NewsPad. The device was supplied for the duration of the Barcelonabased trial, which ended in 1997.
4. Intel announced a Strong ARM based touch screen tablet computer in 1999, under the name WebPAD, the tablet was later re-branded as the "Intel Web Tablet".During the 2000s, Microsoft attempted to define with the Microsoft Tablet PC the tablet personal  computer product concept as a mobile computer for field work in business, though their devicesfailed to achieve widespread usage mainly due to price and usability problems that made them unsuitable outside of their limited intended purpose.In April 2010 Apple Inc. released the iPad, a tablet computer with an emphasis on mediaconsumption. The shift in purpose, together with increased usability, battery life, simplicity, lowerweight and cost, and overall quality with respect to previous tablets, was perceived as defining a new  class of consumer device and shaped the commercial market for tablets in the following year.As a result, two distinctly different types of tablet computing devices exist as of 2012, the TabletPC and the Post-PC tablet, whose operating systems are of different origin.Traditional tablet PCsMain article: Early tablet computersA tablet personal computer (tablet PC) is a portable personal computer equipped with a touchscreen as a primary input device, and running a modified desktop OS designed to be operated and owned by an individual. The term was made popular as a concept presented by  Microsoft in 2000 and 2001 but tablet PCs now refer to any tablet-sized personal computer regardless of the (desktop) operating system. Unlike modern tablet computers, traditional tabletPCs usually had a physical keyboard. Tablet personal computers are mainly based on the x86 IBM-PC architecture and are fullyfunctional personal computers employing a slightly modified personal computer OS (suchasWindows or Linux) supporting their touch-screen, instead of a traditional display, mouse andkeyboard. A typical tablet personal computer needs to be stylus driven, because operating the typicaldesktop based OS requires a high precision to select GUI widgets, such as a close window button."Post-PC" tabletsSee also: Mobile operating systemIn 2005, an internet tablet, the Nokia 770, was introduced. This product line used the Maemo Linuxoperating system. Mobile operating systems have a different kind of interface than the traditional desktop OS, and represent a new type of computing device. These "post-PC" mobileOS tablet computer devices are normally finger driven and most frequently use capacitive touchscreens with multi-touch, unlike earlier stylus-driven resistive touchscreen devices. According to JackGold, tablet computers have "a higher disruptive impact [on PCs] than smartphones do. Smartphones and PCs are complementary, but tablets not as much".The most successful tablet computer is the Apple iPad using the iOS operating system. Its debut in 2010 popularized tablets into mainstream. Samsungs Galaxy Tab and others followed,continuing the now common trends towards multi-touch and other natural user interface features, aswell as flash memory solid-state storage drives and "instant on" warm-boot times; in addition,standard external USB and Bluetooth keyboards can often be used. Most frequently the operatingsystem running on a tablet computer (one not based on the traditional Windows/x86 PC architecture) is a Unix-like OS, such as Darwin, Linux or QNX. Some have 3G mobile telephony capabilities.In forgoing the x86 precondition (a requisite of Windows compatibility), most tablet computersreleased since mid-2010 use a version of an ARM architecture processor for longer battery life versus
5. battery weight, heretofore used in portable equipment such as MP3 players and smartphones.Especially with the introduction of the ARM Cortex family, this architecture is now powerful enough for tasks such as internet browsing, light production work and mobile games.A significant trait of tablet computers not based on the traditional PC architecture is that most mobileapps including third party ones are supplied through online distribution, rather than more traditionalmethods of boxed software or direct sales from software vendors. These sources, known as "appstores", provide centralized catalogues of software from the OS supplier or device manufacturer andfrom outside parties, and allow simple "one click" on-device software purchasing, installation, andupdates. The app store is often shared with smartphones that use the same operating system.Touch user interfaceSamsung Galaxy Tab demonstratingmulti-touchA key and common component among tablet computers is touch input. This allows the user tonavigate easily and intuitively and type with a virtual keyboard on the screen. The first tablet to do thiswas the GRiDPad by GRiD Systems Corporation; the tablet featured both a stylus,a pen-like tool to aid with precision in a touchscreen device as well as an on screen keyboard.The event processing of the operating system must respond to touches rather than clicks of akeyboard or mouse, which allows integrated hand-eye operation, a natural part of the somatosensorysystem. Although the device implementation differs from more traditional PCs or laptops, tablets aredisrupting the current vendor sales by weakening traditional laptop PC sales in favor of the current tablet computers. This is even more true of the "finger driven multi-touch" interface of the morerecent tablet computers, which often emulate the way actual objects behave.Handwriting recognition
6. Chinese characters like this one meaning "person" can be written by handwriting recognition (, Mandarin:rén, Korean: in, Japanese: jin, nin; hito,Cantonese: jan4). The character has two strokes, the first shownhere in dark, and the second in red. The black area represents the starting position of the writing instrument.Some tablet personal computers use a stylus. These tablets often implement handwriting recognition.Tablet computers with finger driven screens usually do not. Finger driven screens are potentiallybetter suited for inputting "variable width stroke based" characters, like Chinese/Japanese/Koreanwriting, due to their built in capability of "pressure sensing". However at the moment not much of thispotential is already used, except in digital art applications like Autodesk Sketchbook for the iPad, and as a result even on tablet computers Chinese users often use a (virtual) keyboard for input.Touchscreen hardwareTouchscreens are usually one of two forms; Resistive touchscreens are passive and can respond to any kind of pressure on the screen. They allow a high level of precision, useful in emulating apointer as is common in tablet computers) but may require calibration to be accurate. Because of the high resolution of detection, a stylus or fingernail is often used for resistive screens. Limited possibilities exist for implementing multi- touch on a resistive touch-screen. As modern tablet computers tend to make heavy use of multi- touch, this technology has faded out on high-end devices where it has been replaced by capacitive touchscreens. Capacitive touchscreens tend to be less accurate, but more responsive than resistive screens. Because they require a conductive material, such as a finger tip, for input, they are not common among (stylus using) Tablet PCs but are more prominent on the smaller scale "tablet computer" devices for ease of use, which generally do not use a stylus, and need multi-touch capabilities.Other touch technology used in tablets include: Palm recognition. It prevents inadvertent palms or other contacts from disrupting the pens input. Multi-touch capabilities, which can recognize multiple simultaneous finger touches, allowing for  enhanced manipulation of on-screen objects.Some professional-grade Tablet PCs use pressure sensitive films that additionally allow pressuresensitivity such as those on graphics tablets.Concurrently capacitive touch-screens, which use finger tip detection can often detect the size of the touched area, and can make some conclusions to the pressure force used, for a similar result.Typical functionsTypical functions of tablet computers in 2012 are: High Definition displays with anti-glare technology Wireless mobile browser functions (using 2G, 3G, 4G or WiFi) E-mail and social media devices (typically with integration apps to bring all feeds into the same view) Potential cell phone functions (Messaging, video calling, speakerphone or headset cellphone uses) Video-teleconferencing (Skype, FaceTime, etc) GPS satellite navigation
7. Stills and video camera functions, photo and video viewing and editing E-book reading and the ability to subscribe to and read daily/weekly/monthly/annual magazines, newspapers, or other periodicals. Read Interactive and traditional graphic novels and comic books Downloadable apps (games, education, utilities) Portable media player function including the ability to watch video (both streaming and locally stored) Weigh around one or two pounds (0.5 - 1 kilogram) Battery life of three to twelve hours depending on usage pattern.Other features Accelerometer: A device that detects the physical movements of the tablet. This allows greater flexibility of use since tablets do not necessarily have a fixed direction of use. The accelerometer can detect the orientation of the tablet relative to the horizontal plane, and movement of the tablet, both of which can be used as an alternative control interface for a tablets software. Ambient light and proximity sensors are additional "senses", that can provide controlling input for the tablet. Storage drive: Large tablets use storage drives similar to laptops, while smaller ones tend to use drives similar to MP3 players or have on-board flash memory. They also often have ports for removable storage such as Secure Digital cards. Due to the nature of the use of tablets, solid- state memory is often preferable due to its better resistance to damage during movement. Some tablet computers utilize cloud storage in conjunction with local storage to increase storage capacity. Large media files such as videos, photos, eBooks, and music stored on the cloud can be streamed seamlessly into the tablet computer using a wireless Internet connection. This frees up the physical drive to hold less gluttonous data associated with applications and utilities. Wireless: Because tablets by design are mobile computers, wireless connections are less restrictive to motion than wired connections. Wi-Fi connectivity has become ubiquitous among tablets. Bluetooth is commonly used for connecting peripherals and communicating with local devices in place of a wired USB connection. 3D: Following mobile phone, there are also 3D slate tablet with dual lens at the back of the tablet  and also provided with blue-red glasses. Docking station: Some newer tablets are offering an optional docking station that has a full size qwerty keyboard and USB port, providing both portability and flexibility.Form factorsTablet computers come in a range of sizes, currently ranging from tablet PCs to PDAs. Traditionaltablet personal computers tend to be as large as laptops and often are the largest usable size formobile tablet computing while the new generation of tablet computers can be much smaller and usea RISC (ARM or MIPS) CPU, and in size can border on PDAs.Slate
8. Writing slate with sponge (~1950). The slate format is named with a metaphor of thislow-tech writing device.Slate computers, which resemble writing slates, are tablet computers without a dedicated keyboard.For text input, users rely on handwriting recognition via an active digitizer, touching an on-screenkeyboard using fingertips or a stylus, or using an external keyboard that can usually be attached viaa wireless or USBconnection.Slate computers typically incorporate small (8.4–14.1 inches/21–36 centimetres) LCD screens andhave been popular in vertical markets such as health care, education, hospitality, aviation (pilot documentation and maps), and field work. Applications for field work often require a tabletcomputer that has rugged specifications that ensure long life by resisting heat, humidity, anddrop/vibration damage. This added focus on mobility and/or ruggedness often leads to elimination ofmoving parts that could hinder these qualities.BookletBooklet computers are dual-touchscreen tablet computers that fold like a book. Typical bookletcomputers are equipped with multi-touch screens and pen writing recognition capabilities. They aredesigned to be used as digital day planners, Internet surfing devices, project planners, music players,and displays for video, live TV, and e-reading.ConvertibleA Lenovo X61 in slate modeConvertible notebooks have a base body with an attached keyboard. They more closely resemblemodern laptops, and are usually heavier and larger than slates.
9. Typically, the base of a convertible attaches to the display at a single joint called a swivel hinge orrotating hinge. The joint allows the screen to rotate through 180° and fold down on top of thekeyboard to provide a flat writing surface. This design, although the most common, creates a physicalpoint of weakness on the notebook.Some manufacturers have attempted to overcome these weak points. The Panasonic Toughbook 19,for example, is advertised as a more durable convertible notebook. (Panasonic also offersthe Toughpad, a water- and shockproof Android tablet.) Meanwhile, the HP EliteBook 2760pconvertible notebook uses a reinforced hinge that protrudes slightly from the rear of the unit. And, onemodel by Acer, the TravelMate C210, has a sliding design in which the screen slides up from theslate-like position and locks into place to provide the laptop mode.Sliding screens were presented at CES 2011. The first product to use it is the Samsung Sliding PC7 Series, a tablet with Intel Atom hardware and a unique sliding screen that allows the product to beused as a laptop or slate tablet when the screen is locked in place covering the whole keyboard. Theconcept must still prove its reliability, but is intended to combine the virtues of tablet PCs with those ofnotebooks. Also presented was the upcoming Inspiron Duo from Dell, which rotates the screenhorizontally when opened. Convertibles like that with hardware specs of a netbook are callednetvertibles.HybridHybrids, a term coined by users of the HP/Compaq TC1000 and TC1100 series, share the features ofthe slate and convertible by using a detachable keyboard that operates in a similar fashion to aconvertible when attached. Hybrids are not to be confused with slate models with detachablekeyboards; detachable keyboards for pure slate models do not rotate to allow the tablet to rest on itlike a convertible.Mini tabletNexus 7, a 7 inch tablet computerMini tablets are smaller and lighter than original larger full-sized tablets. The first successful oneswere introduced by Samsung (Galaxy Tab 7-inch), Barnes and Noble (theNook Tablet), BlackberryPlaybook, and Amazon (the Kindle Fire) in 2011, and by Google (the Nexus 7) in 2012. Most of themwork like a regular tablet, though some of them may not have all the features and functions found inbigger tablet computers. The typical mini tablet is generally 6 or 7 inches (15 - 17.6 cm) diagonal. Minitablets, such as the Toshiba Regza 6-inch tablet and the Sylvania 7-inch, are easier to transport in pockets and purses than the larger 9+ inch types, such as the iPad.Apple has released their own smaller version of the iPad tablet, called the iPad Mini. Its size is 7.9inches, almost 2 inches smaller than the regular size iPad tablet, which is at 9.7 inches. This isthought to compete with other mini-tablets, such as the Nexus 7 and Kindle Fire. Apple announced the new smaller-sized tablet on October 23, 2012.
10. Amazon released an advanced version of the Kindle Fire, called the Kindle Fire HD, on September14, 2012, with higher resolution, more features, and higher capacity, than the original Kindle Fire. The Kindle Fire HD comes in various sizes, and its mini version is also 7 inches.PhabletMain article: PhabletSince 2010, crossover touch-screen devices with screens of 5-inches and above have been released.That size is generally considered too large for a smartphone and too small for a tablet, creating ahybrid category different from the previous common classifications. This hybrid is being calleda phablet by Forbes and Engadget. Phablet is a portmanteau of the words phone and tablet. Popular examples of phablets are the LG Optimus Vu, Samsung Galaxy Note and DellStreak. Samsung claims they had shipped a million units of the Galaxy Note within two months of introducing it.System architectureSee also: Comparison of tablet computers Two major computer architectures dominate the tablet market, Intels x86 and ARM architecture.Intels x86, including x86-64 has provided the brains of the IBM compatible PC since 1981, andApples Mac computers since 2006. The CPUs have been incorporated into a number of tablet PCsover the years and have generally offered greater performance along with the ability to run a fullversions of Microsoft Windows, along with the associated 25 years of associated Windows desktopand enterprise applications on the devices. There are also non-Windows based x86 tablets likethe JooJoo.ARM has been the CPU architecture of choice for: mobile phone, pda, camera, set-top box, dslrouters, television, storage device and tablet computer manufacturers this century. This dominancedates back to the release of the mobile focused and comparatively power / battery efficient 32 bitARM610 SoC (System On a Chip) originally designed for the Apple Newton and Acorn A4 back in1993. The chip was rapidly adopted by the likes of Psion, Palm and Nokia for their own PDA offeringsand later smart phones, camera phones, cameras, etc..... ARMs licensing model has also helped inthis spread and current dominance of the mobile device space; by allowing device manufacturers to:licence, alter and fabricate custom SoC derivatives, specifically tailored to their own products. Thishas helped manufacturers extend battery life and shrink the component count along with the devicessize. The multiple licensee have also ensured multiple generic ARM fabricators are supplying nearidentical products into the market, while encouraging price competition.This has historically forced unitprices down to a fraction of their x86 equivalents, as well as offering the manufacture some insuranceagainst supply insecurities. The architecture has historically had limited support from Microsoft, withonly Windows CE available, but with the release of Windows 8, in 2012, Microsoft has announcedgreater support for the architecture, as well as shipping their own range of ARM based tabletcomputers, branded as the Microsoft Surface, though a later x86 Atom based PRO variant of the Surface will be deliveredOperating systems and vendorsTablets, like regular computers, can run a number of operating systems. These come in two classes,namely traditional desktop-based operating systems and post-PC mobile-based ("phone-like")operating systems.
11. For the former class popular OSs are Microsoft Windows, and a range of Linux distributions. HP isdeveloping enterprise-level tablets under Windows and consumer-oriented tablets under webOS. Inthe latter class the popular variants include Apple iOS, and Google Android. Manufacturers are also testing the market for products with Windows CE, Chrome OS, and so forth.Traditional Tablet PC operating systemsMicrosoftMain article: Microsoft Tablet PCFollowing Windows for Pen Computing, Microsoft has been developing support for tablets running  Windows under the Microsoft Tablet PC name. According to a 2001 Microsoft definition of theterm, "Microsoft Tablet PCs" are pen-based, fully functional x86 PCs with handwriting and voicerecognition functionality. Tablet PCs use the same hardware as normal laptops but add support forpen input. For specialized support for pen input, Microsoft released Windows XP Tablet PC Edition.Today there is no tablet specific version of Windows but instead support is built in to both Home andBusiness versions of Windows Vista and Windows 7. Tablets running Windows get the addedfunctionality of using the touchscreen for mouse input, hand writing recognition, and gesture support.Following Tablet PC, Microsoft announced the UMPC initiative in 2006 which brought Windowstablets to a smaller, touch-centric form factor. This was relaunched in 2010 asSlate PC, to promote tablets running Windows 7, ahead of Apples iPad launch. Slate PCs are expected to benefit frommobile hardware advances derived from the success of the netbooks.While many tablet manufacterurs are moving to the ARM architecture with lighter operating systems, Microsoft has stood firm to Windows. Microsoft has announced Windows 8 which will have the new Metro user interface suited to touchscreen devices such as tablets. .For the first time, Windows will be able to run the ARM architecture because of Windows RT which can run on processors from NVIDIA, Qualcomm and Texas Instruments Microsoft has alsolaunched their own tablet called the Microsoft Surface.Prior to Windows 8 and Windows Phone 8, Windows CE was used to target smart phones in the formof Windows Phone 7. Windows Phone 8 uses the same code as Windows 8. Also, somemanufacturers, however, still have shown prototypes of Windows CE-based tablets running a custom shell.LinuxOne early implementation of a Linux tablet was the ProGear by FrontPath. The ProGear used aTransmeta chip and a resistive digitizer. The ProGear initially came with a version of Slackware Linux,but could later be bought with Windows 98. Because these computers are general purpose IBM PCcompatible machines, they can run many different operating systems. However, the device is nolonger for sale and FrontPath has ceased operations. It is important to note that many touch screensub-notebook computers can run any of several Linux distributions with little customization.X.org now supports screen rotation and tablet input through Wacom drivers, and handwritingrecognition software from both the Qt-based Qtopia and GTK+-based Internet Tablet OS providepromising free and open source systems for future development. KDEs Plasma Active is graphical environments for tablet.Open source note taking software in Linux includes applications such as Xournal (which supportsPDF file annotation), Gournal (a Gnome based note taking application), and the Java-based Jarnal(which supports handwriting recognition as a built-in function). Before the advent of theaforementioned software, many users had to rely on on-screen keyboards and alternative text input
12. methods like Dasher. There is a stand alone handwriting recognition program available, CellWriter,which requires users to write letters separately in a grid.A number of Linux based OS projects are dedicated to tablet PCs, but many desktop distributionsnow have tablet-friendly interfaces allowing the full set of desktop features on the smaller devices.Since all these are open source, they are freely available and can be run or ported to devices thatconform to the tablet PC design. Maemo (rebranded MeeGo in 2010), a Debian Linux based graphicaluser environment, was developed for the Nokia Internet Tablet devices (770, N800, N810 & N900). Itis currently in generation 5, and has a vast array of applications available in both official and usersupported repositories. Ubuntu since version 11.04 has used the tablet-friendly Unity UI, and manyother distributions (such as Fedora) use the also tablet-friendly Gnome shell (which can also beinstalled in Ubuntu if preferred). Previously the Ubuntu Netbook Remix edition was one of the onlylinux distibutions offering a tablet interface with all the applications and features of a desktopdistribution, but this has been phased out with the expansion of Unity to the desktop. A large numberof distributions now have touchscreen support of some kind, even if their interfaces are not well suitedto touch operation.Canonical has hinted that Ubuntu will be available on tablets, as well as phones and smart televisions, by 2014.TabletKiosk currently offers a hybrid digitizer / touch device running openSUSE Linux. It is the firstdevice with this feature to support Linux.Intel and NokiaThe Nokia N800Nokia entered the tablet space with the Nokia 770 running Maemo, a Debian-based Linux distributioncustom-made for their Internet tablet line. The product line continued with the N900 which is the firstto add phone capabilities. The user interface and application framework layer, named Hildon, was anearly instance of a software platform for generic computing in a tablet device intended for internet consumption. But Nokia didnt commit to it as their only platform for their future mobile devices andthe project competed against other in-house platforms. The strategic advantage of a modern platform was not exploited, being displaced by the Series 60.Intel, following the launch of the UMPC, started the Mobile Internet Device initiative, which took thesame hardware and combined it with a Linux operating system custom-built for portable tablets. Intelco-developed the lightweight Moblin operating system following the successful launch of the Atom CPU series on netbooks. Intel is also setting tablet goals for Atom, going forward from 2010.MeeGoMain articles: Maemo, MeeGo, and Tizen
13. MeeGo is a Linux-based operating system developed by Intel and Nokia that supports Netbooks,Smartphones and Tablet PCs. In 2010, Nokia and Intel combined the Maemo and Moblin projects toform MeeGo. The first tablet using MeeGo is the Neofonie WeTab launched September 2010 inGermany. The WeTab uses an extended version of the MeeGo operating system called WeTab OS.WeTab OS adds runtimes for Android and Adobe AIR and provides a proprietary user interfaceoptimized for the WeTab device. On 27 September 2011 it was announced by the LinuxFoundation that MeeGo will be replaced in 2012 by Tizen, an open source mobile operating system.Post-PC operating systemsSee also: Mobile operating systemTablets not following the personal computer (PC) tradition use operating systems in the style of thosedeveloped for PDAs and smartphones.iPadMain articles: iOS (Apple), iPad, and ModBookThe iPad in a caseThe iPad runs a version of iOS which was first created for the iPhone and iPod Touch. Although builton the same underlying Unix implementation as MacOS, the operating system differs radically at thegraphical user interface level. iOS is designed for finger based use and has none of the tiny featureswhich required a stylus on earlier tablets. Apple introduced responsive multi touch gestures, likemoving two fingers apart to zoom in. iOS is built for the ARM architecture, which uses less power, andso gives better battery life than the Intel devices used by Windows tablets. Previous to the iPadslaunch, there were long standing rumors of an Apple tablet, though they were often about a product running Mac OS X and being in line with Apples Macintosh computers. This became partially truewhen a 3rd party offered customized Macbooks with pen input, known as the Modbook. Previous to Apples commercialization of the iPad, Axiotron introduced at Macworld in 2007 anaftermarket, heavily modified Apple MacBook calledModbook, a Mac OS X-based tablet personalcomputer. The Modbook uses Apples Inkwell for handwriting and gesture recognition, and usesdigitization hardware from Wacom. To get Mac OS X to talk to the digitizer on the integrated tablet,the Modbook is supplied with a third-party driver calledTabletMagic; Wacom does not provide driversupport for this device.BlackberryThe BlackBerry PlayBook is a tablet computer announced in September 2010 which runs the BlackBerry Tablet OS. The OS is based on the QNX system that Research in Motion acquiredin early 2010. Delivery to developers and enterprise customers was expected in October 2010. TheBlackBerry PlayBook was officially released to US and Canadian consumers on April 19, 2011.
14. AndroidMain articles: Android (operating system) and Google Chrome OSAn ASUS Eee Pad Transformer running Android 3.2.1 Honeycomb; the keyboard is part of a docking station for thetablet.Googles Linux-based Android operating system is used by tablet manufacturers following its successon smartphones due to its support for low-costARM systems much like Apples iOS. Many were announced in 2010. However, much of Androids tablet initiative came from manufacturers as longas Google primarily focused on smartphones and restricted the App Market from non-phone devices. There is perennial talk of tablet support from Google coming to its web-centric Chrome OS.  Some vendors such as Motorola and Lenovo delayed deployment of their tablets until after 2011, when Android was reworked to include more tablet features. Android 3.0 (Honeycomb) and laterversions are optimized specifically for larger screen sizes, mainly tablets, and have access totheGoogle Play service. Android is the software stack for mobile devices that includes operatingsystem, middleware and key applications.Other vendors sell customized tablets such as Nook and Kindle Fire which are used for mobilecontent from their own Website, and seldom from the larger Google Play system. This has led to market fragmentation.HPHewlett Packard announced the TouchPad, running webOS 3.0 on a 1.2 GHz Snapdragon CPU,would be released in June 2011. On August 18, 2011, HP announced the discontinuation of the TouchPad, due to sluggish sales. HP has announced that they will release webOS as open- source.One Laptop per Child organizationOLPC XO-3 tablet computer
15. The One Laptop per Child (OLPC) organization is developing a new version of the OLPC, stronglyresembling a tablet computer, called the OLPC XO-3, running its "Sugar" operating system, based on Linux. The new XO-3 will be based on ARM technology from Marvell.India OLPC plans to introduce a tablet computer to India for $100. Nicholas Negroponte, Chairman ofOLPC, has invited the Indian researchers to MIT to begin sharing the OLPC design resources for their tablet computers. OLPC has been awarded a grant for an interim step to their next-generation tablet, OLPC XO-3.Developing software for tablet computersSee also: Mobile developmentThe new class of devices heralded by the iPad has spurred the tendency of a walledgarden approach, wherein the vendor reserves rights as to what can be installed. The softwaredevelopment kits for these platforms are restricted and the vendor must approve the final applicationfor distribution to users. These restrictions allow the hardware vendor to control the kind of softwarethat can be used and the content that can be seen in the devices; this can be used to reduce theimpact of malware on the platform and to provide material of approved content rating, and also toexclude software and content from competing vendors. The walled garden approach to applicationdevelopment has proven to be a competitive advantage for the iPad over HPs TouchPad, triggeringHPs withdrawal from the industry, due in large part to sluggish TouchPad sales after only 49 days on the market.Barnes and Noble adopted the walled garden strategy with its Nook Color and Nook Tablet e-bookreader tablets, which FastCompany writer Austin Carr refers to as "an odd idea of progress", sinceB&N lacks the competitive advantages of number of apps and price enjoyed by Apple andAmazon.com. B&Ns strategy became especially notable following pronouncements by B&Nexecutives criticizing Amazon.coms walled garden approach, which they contrasted with B&Nsemphasis on user choice. Specifically, in a mid-December interview, B&N CEO William Lynch calledAmazons Kindle Fire a "deficient" media tablet designed as a "vending machine for Amazonsservices", and a device aimed to "lock consumers into [Amazons] ecosystem". In contrast, B&NsNook Tablet gave users choice and a much more "open" experience which, according to Lynch, maybe one of the Nook Tablets most significant selling points. In the same interview, B&Ns director ofdeveloper relations Claudia Romanini reiterated, "Its about giving [consumer] choice and range. Whatwe mean in terms of choice, is that we dont lock a customer into a service and say, This is the way youre going to get your media.". Indeed, Nook Tablets shipped until December 2011 were lauded by reviewers and users for permitting users to download and sideload third-party apps, but, oneweek before Christmas, B&N began pushing an automatic, over-the-air firmware update 1.4.1 to NookTablets that removed users ability to gain root access to the device and the ability to sideload apps from sources other than the official Barnes and Noble app store (without modding).Proponents of open source software deem that these restrictions on software installation and lack ofadministrator rights make this category one that, in their view, cannot be properly named "personal computers". Some newer tablet computers using mobile operating systems dont use the walled garden concept, and are like personal computers in this regard.Sales
16. Among tablets available in the market,Apples iPad (left) is the top-selling tablet with 100 million units sold by midOctober 2012, followed by Amazons Kindle Fire(right) with 7 million.According to a survey conducted by the Online Publishers Association (OPA) in March 2012, 31%percent of Internet users in the United States own a tablet, up from 12% in 2011. The OPA estimatesthat tablet ownership among the U.S. Internet population will rise to 47%. The survey also found that72% of tablet owners had an iPad, while 32% had an Android tablet in 2011; and by 2012, Androidtablet adoption has increased, with 52% of tablet owners using an iPad, while 51% use an Android-powered tablet. The percentages do not add up to 100% because some tablet owners own/use more than one type of tablet. As of October 2012, the top-selling tablet is Apples iPad with 100 million units sold, and accordingto estimates by Forrester Research, the iPad family is followed by Amazons Kindle Fire with 7 million, Barnes and Nobles Nook 5 million, and Googles Nexus 7 with 3 million units. For the first time inhistory, display screen shipments for tablets exceeded shipments for laptop display screens, as of October 2012.