A: The Chicago police department in the 1930s pioneered the use of a form of mobile telephone (two way radio) to stay ahead of prohibition gangsters. The mobile phone or the cellular phone as we know today was invented by Dr. Martin Cooper of Motorola. It was used for the first time in 1973 in a demonstration call, which was made by cooper to his rival Joel Angel, the head of research at Bell Laboratories. The frequency switching system that allows cell phones to work was invented in the 1930's by Hollywood beauty Hedy Lamarr. The Bell Laboratories built a prototype cell system by 1977 which was tested by two thousand selected customers.
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