IPhone 4S announced iPhone 5s and iPhone 5c. This was unusual for Apple as an upper case 'S' had been used since the introduction of the iPhone 3GS in 2009. On September 9, 2014, the iPhone 4S was officially discontinued following the reveal of the iPhone 6 and the iPhone 6 Plus. However, 4S production did continue for developing markets until February 17, 2016. On June 13, 2016, following the release of iOS 10, Apple dropped support on the iPhone 4S, making iOS 9.3.5 the last version available for the device. The runs iOS, Apple's mobile operating system. The user interface of
IPhone 3G mailbox feature, homescreen folders to better organize apps, playlist creation, and other enhancements. This update was widely criticized for slow performance on iPhone 3G, though September 2010's iOS 4.1 release resolved this problem. However, unlike more modern iOS devices, this update again does not provide iPhone 3G owners with access to important features, in this case the Game Center application. On November 22, 2010, the iPhone 3G received the iOS 4.2 software update (as iOS 4.2.1), which introduced features such as YouTube voting, and security fixes. However, the iPhone 3G is unable to use many features included in this update,