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 laptop 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 PenLite, 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 the iPad was developed 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.
Screen and input
The iPad’s touchscreen display is a 9.7 in (25 cm) liquid crystal display (1024 × 768 pixels) with fingerprint-resistant and scratch-resistant glass. 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.
Ars Technica noted the similarity between the iPad and Star Trek’s fictional PADD tablet computer, both in name and functionality.
The iPad can use Wi-Fi network trilateration from Skyhook Wireless to provide location information to applications such as Google Maps. The 3G model contains A-GPS to allow its position to be calculated with GPS or relative to nearby cellphone towers; it also has a black plastic accent on the back side to improve 3G radio sensitivity.
For wired connectivity, the iPad has a proprietary Apple dock connector; it lacks the Ethernet and USB ports of larger computers.
Audio and output
The iPad has two internal speakers that push mono sound through two small sealed channels to the three audio ports carved into the bottom-right of the unit. A volume switch is on the right side of the unit.
A 3.5-mm TRS connector audio-out jack on the top-left corner of the device provides stereo sound for headphones with or without microphones and/or volume controls. The iPad also contains a microphone that can be used for voice recording.
The built-in Bluetooth 2.1 + EDR interface allows wireless headphones and keyboards to be used with the iPad. However, the iOS does not currently support file transfer via Bluetooth. iPad also features 1024 x 768 VGA video output for connecting an external display or television.
Power and battery
The iPad uses an internal rechargeable lithium-ion polymer battery (LiPo). The batteries are made in Taiwan by Simplo Technology, which makes 60% of them, and Dynapack International Technology. The iPad is designed to be charged with a high current (2 amperes) using the included USB 10-watt (0.013 hp) power adapter. While it can be charged by a standard USB port from a computer, these are limited to 500 milliamperes (half an amp). As a result, if the iPad is turned on while connected to a normal USB computer port, it may charge much more slowly, or not at all. High-power USB ports found in newer Apple computers and accessories provide full charging capabilities.
Apple claims that the iPad’s battery can provide up to 10 hours of video, 140 hours of audio playback, or one month on standby. Like any battery technology, the iPad’s LiPo battery loses capacity over time, but is not designed to be user-replaceable. In a program similar to the battery-replacement program for the iPod and the original iPhone, Apple will replace an iPad that does not hold an electrical charge with a refurbished iPad for a fee of $99 (plus $6.95 shipping).
Storage and SIM
The iPad was released with three options for internal storage size: a 16, 32, or 64 GB flash drive. All data is stored on the flash drive and there is no option to expand storage. Apple sells a camera connection kit with an SD card reader, but it can only be used to transfer photos and videos.
The side of the Wi-Fi + 3G model has a micro-SIM slot (not mini-SIM). Unlike the iPhone, which is usually sold locked to specific carriers, the 3G iPad is sold unlocked and can be used with any compatible GSM carrier. Japan is the exception to this, where the iPad 3G is locked to Softbank. In the U.S., data network access via T-Mobile’s network is limited to slower EDGE cellular speeds because T-Mobile’s 3G Network uses different frequencies.