Micro-light-emitting diodes (Micro-LEDs) based on gallium nitride (GaN) materials offer versatile platforms for various applications, including displays, data communication tools, photodetectors, and sensors. In particular, the introduction of Micro-LEDs in the optoelectronic industry enables the development of novel short-distance wireless communication applications for the Internet of Things as well as near-to-eye displays for virtual reality and augmented reality. Micro-LEDs used in conjunction with colloidal quantum dots (QDs) as color-conversion layers provide efficient full-color displays as well as white LEDs for high-speed visible light communications (VLCs). Here, the latest progress on full-color Micro-LED displays with a printed QD color conversion layer, GaN material-based Micro-LEDs for VLC systems, and the photostability of novel QD materials for Micro-LEDs is comprehensively reviewed. Outlooks on the efficiency of Micro-LEDs with sizes ≤10 µm, QD stability issues, and flexible Micro-LED displays are also provided.