iPad is an iOS-based line of tablet computers designed and marketed by Apple Inc. The first iPad was released on April 3, 2010; the most recent iPad models, the iPad Air 2 and iPad Mini 3, were released on October 22, 2014. The user interface is built around the device's multi-touch screen, including a virtual keyboard. The iPad includes built-in Wi-Fi and cellular connectivity on select models. As of June 2014, there have been over 200 million iPads sold. An iPad can shoot video, take photos, play music, and perform Internet functions such as web-browsing and emailing. Other functions—games, reference, GPS navigation, social networking, etc.—can be enabled by downloading and installing apps. As of October 2013, the App Store has more than 475,000 native apps by Apple and third parties.
(Source: http://en.wikipedia.org/wiki/IPad#Model_comparison)
