Android is a mobile operating system initially developed by Android Inc. Android was bought by Google in 2005 . [ 5 ] Android is based upon a modified version of the Linux kernel . Google and other members of the Open Handset Alliance collaborated on Android's development and release. [ 6 ] [ 7 ] The Android Open Source Project (AOSP) is tasked with the maintenance and further development of Android. [ 8 ] In Q4 2010 the Android O.S. was the world's best-selling smartphone platform, dethroning Nokia 's Symbian from the 10 year top position, according to Canalys. [ 9 ] [ 10 ] Android has a large community of developers writing application programs ("apps") that extend the functionality of the devices. There are currently over 200,000 apps available for Android. [ 11 ] Android Market is the online app store run by Google, though apps can be downloaded from third-party sites ( AT&T permits third-party apps only on their Aria phone [ 12 ] ). Developers wr