IOS(redirected from iOS 4)
Internetworking Operating System
IOS(1) (iOS) (IDevice Operating System) The primary control program in Apple's iPhone, iPad and iPod touch. iOS apps are programmed in Objective-C and Swift. The Mac uses the macOS operating system (formerly OS X), not iOS. See iDevice, iOS device, iOS versions, CarPlay, Objective-C, Swift and Mac OS X.
(2) (Internetwork Operating System) The primary control program in Cisco routers. Widely used, IOS is robust system software that supports the common functions in all products based on the CiscoFusion architecture. See Cisco.
(3) (Integrated Office System) See office automation.