Mobile phone commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion—enough to provide one for every person on Earth. In first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple, and Huawei, with smartphone sales represented 78 percent of total mobile phone sales. For feature phones (or "dumbphones") , the largest were Samsung, Nokia, and Alcatel. A handheld mobile radio telephone service was envisioned in the early stages of radio engineering. In 1917, Finnish inventor Eric Tigerstedt filed a patent for a "pocket-size folding telephone with a very thin carbon microphone".
Mobile phone features there are smartphones that offer reverse wireless charging. Most mobile phone networks are digital and use the GSM, CDMA or iDEN standard which operate at various radio frequencies. These phones can only be used with a service plan from the same company. For example, a Verizon phone cannot be used with a T-Mobile service, and vica versa. A multi-mode phone operates across different standards whereas a multi-band phone (also known more specifically as dual, tri or quad band) mobile phone is a phone which is designed to work on more than one radio frequency. Some multi-mode phones can operate on