Modern smart phones and tablet computers typically incorporate multiple wireless services at different frequency bands ranging from FM radio to LTE. At the same time, an increasing number of designs utilize more than one antenna to enhance sensitivity and suppress cross-talk. Both trends place the miniature RF solid-state switches in an increasingly crucial role in smart mobile device RF front end designs. This paper will give an overview of both high and low throw-count RF switches used in different circuit locations in a typical mobile device design, and discuss how each performance specification and design feature will impact on the overall performance of your system. In addition, this paper will dive deeper inside each RF switch module and reveal current and future trends in core RF switching technologies.