iPad

The iPad is a tablet computer designed, developed and marketed by Apple primarily as a platform for audio-visual media including books, periodicals, movies, music, games, and web content. At about 1.5 pounds (680 grams), its size and weight fall between those of contemporary smartphones and Apple computers. Apple released the iPad in April 2010, and sold 3 million of the devices in 80 days.

According to a report released by Strategy Analytics, the Apple iPad had gained a 95 percent share of Tablet PC sales at the end of second quarter 2010. During the second quarter 2010, Apple had sold 4.19 million iPads around the world.

The iPad runs the same operating system as the iPod Touch and iPhone—and can run its own applications as well as iPhone applications. Without modification, it will only run programs approved by Apple and distributed via its online store.

Like iPhone and iPod Touch, the iPad is controlled by a multitouch display—a departure from most previous tablet computers, which used a pressure-triggered stylus—as well as a virtual onscreen keyboard in lieu of a physical keyboard. The iPad uses a WI-FI data connection to browse the Internet, load and stream media, and install software. Some models also have a 3G wireless data connection which can connect to HSPA data networks. The device is managed and synced by iTunes on a personal computer via USB cable.

Media reaction to the device has generally been neutral or positive, with more positive reaction after the device was launched.

Apple's first tablet computer was the Newton Messagepad 100, introduced in 1993, which led to the creation of the ARM6 processor core with Acorn Computers. Apple also developed a prototype PowerBook Duo-based tablet, the Pen Lite, but in order to avoid hurting MessagePad sales did not sell it. Apple released several more Newton-based PDAs, and discontinued the last, the MessagePad 2100, in 1998.

With the success of the introduction of portable music player iPod in 2001, Apple re-entered the mobile-computing market in 2007 with the iPhone. Smaller than the iPad but featuring a camera and mobile phone, it pioneered the multitouch finger-sensitive touchscreen interface of Apple's mobile operating system—iOS. By late 2009, the iPad's release had been rumored for several years. Mostly referred to as "Apple's tablet", iTablet and iSlate were among the speculated names. The iPad was announced on January 27, 2010, by Steve Jobs at an Apple press conference at the Yerba Buena Center For The Arts in San Francisco.

Jobs later admitted that development started on the iPad before the iPhone. Upon realizing that it would work just as well as a mobile phone, Jobs put development of the iPad on hold and decided to develop the iPhone instead.

The iPad's touchsreen display is a 9.7 in (25 cm) liquid crystal display (1024 × 768 pixels) with finger-print resistant and scratch-resistant glass. Steve Jobs backed the choice of screen size, saying a 7-inch screen would be "too small to express the software." He said 10 inches was the minimum for a tablet screen. Like the iPhone, the iPad is designed to be controlled by bare fingers; normal gloves and styli that prevent electrical conductivity may not be used, although there are special gloves and capacitive styli designed for this use.

The display responds to two other sensors: an ambient light sensor to adjust screen brightness and a 3-axis accelerometer to sense iPad orientation and switch between portrait and landscape modes. Unlike the iPhone and iPod touch built-in applications, which work in three orientations (portrait, landscape-left and landscape-right), the iPad built-in applications support screen rotation in all four orientations (the three aforementioned ones along with upside-down), meaning that the device has no intrinsic "native" orientation; only the relative position of the home button changes.

In total there are four physical switches on the iPad, including a home button below the display that returns the user to the main menu, and three plastic physical switches on the sides:wake/sleep and volume up/down, plus a third which, as of iOS 4.2, acts as a mute switch. Initially this switch was utilized to lock out the screen rotation function (reportedly to prevent unintended rotation when the user is lying down). However, with the iOS 4.2 update, this functionality was removed and rotation lock is now controlled with a software toggle via the iOS task switcher. There is no means to reassign the physical switches functionality in the official iOS release.