Android is a Linux-based operating system for mobile phones and tablets, developed by Google in partnership with the Open Handset Alliance, a consortium of hardware, software, and telecommunication companies. Android Apps are available for download through Google Play or third-party sites. As of September 2012, there were more than 675,000 apps available for Android and the estimated number of applications downloaded from Google Play was 25 billion. Android has become the world’s leading smartphone platform, with a worldwide smartphone market share of 68% at the second quarter of 2012.
In 2010, Google launched its first Android device, the Nexus One smartphone, manufactured by HTC. The Nexus series has since been extended to include the Galaxy Nexus phone and the Nexus 7 tablet, manufactured by Samsung and Asus respectively. The Nexus phones and tablets are Google’s flagship Android devices, demonstrating the latest software and hardware features.
The Android interface is based on touch inputs that correspond loosely to real-world actions, like swiping, tapping, pinching and reverse pinching to manipulate on-screen objects. Hardware components such as accelerometers, gyroscopes and proximity sensors can respond to other user actions, eg adjusting the screen from portrait to landscape to match the orientation of the device.
Android homescreens display app icons, which launch the associated app, and widgets, which display live content such as the weather forecast or the user’s email inbox. A homescreen may consist of several pages that the user can swipe back and forth between. At the top of the screen there is a status bar, which displays information about the device and its connectivity. The status bar can be pulled down to show a notification screen where apps display important information or updates.