(1) (iOS) (
IDevice
Operating
System) The primary control program in Apple's iPhone and iPad until 2019 when the iPad began to use iPadOS. iOS apps are programmed in Objective-C and Swift. All of the current operating systems from Apple evolved from Unix, including iOS, iPadOS and macOS (formerly OS X). See
iPadOS,
iDevice,
iOS device,
iOS versions,
CarPlay,
Objective-C,
Swift,
macOS and
Unix.
(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.