IPhone 3GS and quad-band GSM/GPRS/EDGE radio, the 3GS also adds support for 7.2 Mbit/s HSDPA allowing faster downlink speeds though upload speeds remain the same as Apple had not implemented the HSUPA protocol. Other updates include the addition of a built-in Nike+iPod sensor which eliminates the need for an external sensor and allows native Nike+iPod support. The Bluetooth server on the iPhone 3GS has also been slightly improved adding support for Bluetooth 2.1 specifications. Voice Control was introduced as an exclusive feature of the iPhone 3GS and allows for the controlling of the phone and music features of the phone by voice.
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.