Google's mobile operating system Android has won plenty of adherents among cellphone makers and gadget manufacturers since its 2007 debut. Now defense contractor Raytheon is preparing it for a more urgent mission: saving lives in places like Afghanistan and Pakistan. Using Android software tools, Raytheon engineers have built a basic application for military personnel that combines maps with a buddy list. Raytheon calls the entire framework the Raytheon Android Tactical System, or RATS for short. Mark Bigham, a vice president of business development in Raytheon's Intelligence and Information Systems unit, says the company selected Android because its open source nature made developing applications easy.