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 5C 2014) over the iPhone 5C, during the period that both phones were sold side by side. The 8 GB version of the iPhone 5C, released in 2014, was described as "unusable" as only 4.9GB is available to the user after installing iOS 8; in contrast to iPhone 5S which offers a minimum of 16 GB storage. The iPhone 5C was regarded as too expensive to compete with affordable flagship smartphones such as the Nexus 5 and OnePlus One, or smartphones designed for developing markets such as the Moto G. The iPhone 5S and 5C sold over nine million units in