OnStar Corporation's a subsidiary of General Motors that provides subscription-based communications, in-vehicle security, hands free calling, navigation, and remote diagnostics systems throughout the United States and Canada. OnStar services are only available currently on vehicles manufactured by General Motors. The service's available for all vehicles that've the factory-installed OnStar hardware. OnStar's known as ChevyStar in Latin American markets. The service currently has more than five… (More on Onstar)