Android is a mobile operating system initially developed by Android Inc., a firm purchased by Google in 2005. Android is based upon a modified version of the Linux kernel. It is a participant in the Open Handset Alliance. Unit sales for Android OS smart phones ranked first among all Smartphone OS handsets sold in the U.S. in the second and third quarter of 2010, with a third quarter market share of 43.6%. Android has a large community of developers writing application programs (“apps”) that extend the functionality of the devices. The program helps to build on a java platform and develop android applications.