(1) (iOS) (
IDevice
Operating
System) The primary control program in Apple's iPhone, iPad and iPod touch until 2019 when the iPad switched to its own OS (see
iPadOS). 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
macOS.
(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.