Visible-color-tunable light-emitting diodes (LEDs) with electroluminescent color that changes continuously from red to blue by adjusting the external electric bias are fabricated using multifacetted GaN nanorods with anisotropically formed 3D InGaN multiple-quantum wells. Monolithically integrated red, green, and blue LEDs on a single substrate, operating at a fixed drive current, are also demonstrated for inorganic full-color LED display applications.