The iPad (/ˈaɪpæd/ eye-pad) 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 are the 9.7-inch iPad Pro released on March 31, 2016 and the iPad Mini 4, released on September 9, 2015. 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 January 2015, there have been over 250 million iPads sold.[7] IPad tablets are second most popular, by sales, against Android-based ones, since 2013, when Android tablet sales increased by 127%.[18]
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.[19]
There have been six versions of the iPad. The first generation established design precedents, such as the 9.7-inch screen size and button placement, that have persisted through all models. The 2nd generation iPad (iPad 2) introduced a whole new design which also added a dual-core Apple A5 processor and VGA front-facing and 720p rear-facing cameras designed for FaceTime video calling, and dramatically reduced the thickness of the device. The third generation added a Retina Display, the new Apple A5X processor with a quad-core graphics processor, a 5-megapixel camera, HD 1080p video recording, voice dictation, and 4G (LTE). The fourth generation added the Apple A6X processor and replaces the 30-pin connector with an all-digital Lightning connector. The iPad Air added the Apple A7 processor and the Apple M7 motion coprocessor, and reduced the thickness for the first time since the iPad 2. The iPad Air 2 added the Apple A8X processor, the Apple M8 motion coprocessor, an 8-megapixel camera, and the Touch ID fingerprint sensor, and further reduced the thickness.
There have been four versions of the iPad Mini. The first generation features a reduced screen size of 7.9 inches and features similar internal specifications as the iPad 2 except it uses the Lightning connector. The iPad Mini 2 features the Retina Display, the Apple A7 processor and the Apple M7 motion coprocessor, closely matching the internals specifications of the iPad Air. The iPad Mini 3 features the Touch ID fingerprint sensor. The iPad Mini 4 features the Apple A8 and the Apple M8 motion coprocessor.
