The iPad is a tablet computer designed and marketed by Apple for Internet browsing , media consumption, gaming, and light content creation . Released in April 2010, it established a new class of devices between smart phones and laptops. As of may 3, 2010, Apple had sold 1 million iPads.
Similar to the older ( and smaller ) iPod Touch and iPhone , the iPad runs a modified version of the iPhone OS and is controlled by a multi-touch LCD sensitive to fingertips , not a stylus. It runs iPad - specific applications as well as those written for the iPhone and iPod touch, including e- book readers.
The iPad uses Wi-Fi or its 3G data connection to browse the Internet, load and stream media, and install software, A USB cable is required to sync the iPad with iTunes on a personal computer.
SCREEN AND INPUT
The touchscreen is a 25 cm (9.7 in ) liquid crystal display (1024*768 pixels , 132 ppi, XGA ) with fingerprint-resistant and scratch-resistant glass. Like the iPhone, the iPadis designed to be controlled by bare fingers , not gloves and styli that prevent electrical conductivity (although there are gloves and 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 , which work in three orientations, the iPad supports screen rotation in all four orientations , meaning that the device has no intrinsic "up" or "down" ; only the position of the home button changes. Most iPad applications support both portrait and landscape mode.
The iPad has a switch to lock out this screen rotation function ( reportedly to prevent unintended rotation when the user is lying down) . There are a total of four physical switches, 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 , along with the screen rotation lock.
CONNECTIVITY
The iPad can use Wi-Fi network trilateration from sky hook wireless to provide location information to applications such as Google Maps. The 3G model contains A-GPS while both models have a digital compass.
The back of the Wi-Fi model ipad is made of contoured aluminium with black plastic buttons. The Wi-Fi+ 3G model also has a black plastic accent on top of the device which helps with 3G radio sensitivity . The ipad does not have any ports for wired connectivity.