IPhone its older iPhones when issuing operating system upgrades. It has spurred allegations that the firm has been using this as a tactic to prompt users of older iPhones to buy newer models. Up to the iPhone 4, all iPhone models, as well as other iOS devices were manufactured exclusively by Foxconn, based in Taiwan. In 2011, after Tim Cook became CEO of the company, Apple changed its outsourcing strategy, for the first time increasing its supply partners. The iPhone 4s in 2012 was the first model which was manufactured simultaneously by two stand-alone companies: Foxconn as well as Pegatron, also
IPhone accessories for phone calls and voice control of certain devices. Users can adjust volume, control music and video playback (play/pause and next/previous,) and record voice memos on supported iPod and iPhone models and Mac computers. There have been many reports of moisture problems with the remote/mic earbuds. The original iPhone and iPhone 3G came with the iPhone Stereo Headset, a push-button and microphone on the right side of the headphones (there is no volume control, and only limited control of calls). A series of docks released for the iPhone 5, 5s, and 5c, were announced and released on September 10, 2013.