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 overuse on the human's psychological mind and social communication. Mobile phone users may encounter stress, sleep disturbances and symptoms of depression, especially young adults. Consistent phone use can cause a chain reaction, affecting one aspect of a user's life and expanding to contaminate the rest. It usually starts with social disorders, which can lead to depression and stress and ultimately affect lifestyle habits such as sleeping right and eating right. According to research done by Jean M. Twenge, a professor of psychology at San Diego State University, there is a correlation between mobile phone overuse and depression. According to Twenge and