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 4 antenna issues, 72% of iPhone 4 users say that they are "very satisfied" with their iPhone 4 according to an August 2010 survey by ChangeWave Research. The iPhone 4 model continued to be sold unchanged up until September 2013. In 2011, two iPhone 4 units equipped with a special application were taken to the International Space Station aboard the Space Shuttle on the STS-135 mission. The devices were used in various experiments, utilizing sensors and a special app. IPhone 4 The iPhone 4 is a smartphone that was designed and marketed by Apple Inc. It is the fourth generation iPhone,