Apple iOS9 release: A review of the past iOS highlights

Apple's operating system, iOS, has changed a lot since it was officially released in 2007. Many people should remember IOS7 's iconic flat design, but it's hard to remember all the changes that iOS has made over the years. But never mind, this article will review the changes brought about by each generation of iOS systems.

IPhone OS 1.0

Apple officially released its first iphone on January 9, 2007, and Jobs said the operating system it was running was a different version of OS X. When the system was later opened to developers, Apple called it "the IPhone OS."

The first iphone OS has no App Store and users can't download any third-party apps.

IPhone OS 2.0

The second-generation iphone OS was released with the iphone 3G in July 2008 and supported the first iphone upgrades. The new operating system has officially brought the app Store and added support for third-party applications.

IPhone OS 3.0

iphone OS 3.0 was released in June 2009 and is pre-installed in the iphone 3GS. This version of the upgrade brings with it the ability to copy and paste, and introduces the horizontal screen keyboard. But today most iphone users are more likely to type in the vertical screen mode.