iPad ( EYE-pad) is a line of tablet computers designed, developed and marketed by Apple Inc., which run the iOS mobile operating system. The first iPad was released on April 3, 2010; the most recent iPad models are the iPad (2018), released on March 27, 2018 and the 10.5-inch (270 mm) and 12.9-inch (330 mm) 2nd generation iPad Pro released on June 13, 2017. The user interface is built around the device's multi-touch screen, including a virtual keyboard. All iPads can connect via Wi-Fi; some models also have cellular connectivity.
As of May, 2017, Apple has sold more than 360 million iPads, though sales peaked in 2013. It is the most popular tablet computer by sales as of the second quarter of 2018.
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 March, 2016, the App Store has more than one million apps for the iPad by Apple and third parties.
There have been eight versions of the iPad. The first generation established design precedents, some of which, such as the home button placement, have persisted through all models. The 2nd-generation iPad (iPad 2) introduced a new thinner design, a dual-core Apple A5 processor, and VGA front-facing and 720p rear-facing cameras designed for FaceTime video calling. 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 replaced 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. The iPad introduced in 2017 added the Apple A9 processor, while sacrificing some of the improvements the iPad Air 2 introduced in exchange for a lower launch price.
There have been four versions of the iPad Mini, all of which have a screen size of 7.9 inches (20 cm). The first generation has similar internal specifications to the iPad 2 but uses the Lightning connector instead. The iPad Mini 2 added the Retina Display, the Apple A7 processor, and the Apple M7 motion coprocessor, closely matching the internal specifications of the iPad Air. The iPad Mini 3 added the Touch ID fingerprint sensor. The iPad Mini 4 features the Apple A8 and the Apple M8 motion coprocessor.
There have been two generations of the iPad Pro. The first generation came with 9.7" and 12.9" screen sizes, while the second came with 10.5" and 12.9" sizes. The iPad Pros have unique features such as the Smart Connector, which are exclusive to this series of iPads.