Android is a mobile operating system developed by Google. It is used by several smartphones, such as the Motorola Droid, the Samsung Galaxy, and Googles own Nexus One. The Android operating system (OS) is based on the open Linux kernel. Unlike the iPhone OS, Android is open source, meaning developers can modify and customize the OS for each phone. Therefore, different Android-based phones may have different graphical user interfaces GUIs even though they use the same OS. Android phones typically come with several built-in applications and also support third-party programs. Developers can create programs for Android using the free Android SDK (Software Developer Kit). Android programs are written in Java and run through Googles "Davlik" virtual machine, which is optimized for mobile devices. Users can download Android "apps" from the online Android Market.
The version history of the Android mobile operating system began with the release of the Android beta in November 2007. The first commercial version, Android 1.0, was released in September 2008. Android is under ongoing development by Google and the Open Handset Alliance, and has seen a number of updates to its base operating system since its original release. These updates typically fix bugs and add new features. As of 2013, over 500 million active devices use the Android OS worldwide. The most recent major Android update was Jelly Bean 4.2, which was released on commercial devices in November 2012.
Android 4.2 takes the speed and simplicity of Jelly Bean to a different level – a completely new camera experience that’s beyond smart, a new form of typing that helps you power through your messages, and much more.