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 towers near the owner of the phone. The movements of a mobile phone user can be tracked by their service provider and if desired, by law enforcement agencies and their governments. Both the SIM card and the handset can be tracked. China has proposed using this technology to track the commuting patterns of Beijing city residents. In the UK and US, law enforcement and intelligence services use mobile phones to perform surveillance operations. They possess technology that enables them to activate the microphones in mobile phones remotely in order to listen to conversations which take place near the phone. Hackers