IOS refers to the operating system software that Apple Inc. developed for their mobile devices. All Apple mobile devices such as the IPhone operate on the IOS.
It was initially known as the IPhone Operating System(IOS). IOS is considered the second most widely used operating system in the world, it was first rolled out in 2007.
Since its launch in 2007 for the first generational iPhone, Apple Inc. has made a lot of improvements to both the operating system and their phone models. The latest IPhone on the market is the IPhone 13 which was released on September 24, 2021.
Apple Inc. is very committed to offering the best performance to its customers and as result, they regularly roll out new IOS. They recently released the latest IOS 15.3 on the 26th of January, 2022.