Rapid advancement of modern electronics has pushed the limits of traditional thermal management techniques. Novel approaches to the manipulation of the flow of heat in electronic systems have potential to open new design spaces. Here, the field of thermal metamaterials as it applies to electronics is briefly reviewed. Recent research and development of thermal metamaterial systems with anisotropic thermal conductivity for the manipulation of heat flow in ultra-thin composites is explained. An explanation of fundamental experimental studies on heat flow control using standard printed circuit board (PCB) technology follows. From this, basic building blocks for heat flux cloaking, focusing, and reversal are reviewed, and their extension to a variety of electronics applications is emphasized. While device temperature control, thermal energy harvesting, and electrothermal circuit design are the primary focus, some discussion on the extension of thermal guiding (TG) structures to device-scale applications is provided. In total, a holistic view is offered of the myriad of possible applications of thermal metamaterials to heat flow control in future electronics.