Android is a Linux-based operating system designed primarily for touchscreen mobile devices such as smartphones and tablet computers, developed by Google in conjunction with the Open Handset Alliance.^[2] Initially developed by Android Inc, whom Google financially backed and later purchased in 2005,^[9] Android was unveiled in 2007 along with the founding of the Open Handset Alliance, a consortium of 86 hardware, software, and telecommunication companies devoted to advancing open standards for mobile devices.^[10]
Google releases the Android code as open-source, under the Apache License.^[11] The Android Open Source Project (AOSP), lead by Google, is tasked with the maintenance and further development of Android.^[12] Additionally, Android has a large community of developers writing applications ("apps") that extend the functionality of devices. Developers write primarily in a customized version of Java,^[13] and apps can be downloaded from online stores such as Google Play (formerly Android Market), the app store run by Google, or third-party sites. In June 2012, there were more than 600,000 apps available for Android, and the estimated number of applications downloaded from Google Play was 20 billion.^[14]
The first Android-powered phone was sold in October 2008,^[15] and by the end of 2010 Android had become the world's leading smartphone platform.^[16] It had a worldwide smartphone market share of 59% at the beginning of 2012,^[17] and as of third quarter 2012, there were 500 million devices activated and 1.3 million activations per day.[1