Graphene has a wide range of attractive electrical and mechanical properties. This unique blend of properties make it a good candidate for emerging and future device technologies, such as sensors, high frequency electronics, and energy storage devices. In this review paper, each of the aforementioned applications will be explored along with demonstrations of their operating principles. Specifically, we explore pressure and humidity sensors, graphene base transistor for high frequency applications, and supercapacitors. In addition, this paper provides a general overview of these graphene technologies and, in the case of pressure and humidity sensors, benchmarking against other competing technologies. This paper further shows possible and prospective paths that are suitable for future graphene research to take.