Magnetic-configuration-dependent electrical characteristics of magnetic-tunnel-junction-based three-terminal devices have been computed in the framework of the parabolic band model. Besides their fundamental interest in measuring the properties of nonequilibrium spin-dependent hot-electron transport, three-terminal devices appear to be good candidates for a new generation of magnetic-field-dependent devices. The control of the hot-electron transmission in a double-tunnel junction is a keystone to ensure asymmetric diodes or hot-electron magnetic-field-dependent transistors. Based on a basic description of electron scattering and noncoherent transport in the structure but using electronic parameters extracted from experiments, we assess the functionalities of those devices.