We have fabricated the first InAs‐channel field‐effect transistor, which shows a transconductance of 180 mS/mm at 1 V drain‐source bias (77 K). An improved buffer layer could significantly improve the device performance. In addition, we propose a new broken‐gap heterojunction field‐effect transistor based on these materials that could provide an order of magnitude higher transconductance compared to existing device configurations based on AlGaAs/GaAs.