This paper proposes a reversible color transform for 16-bit-color (hicolor) picture coding. The work is motivated by the increasing needs of multimedia applications on low-end devices such as mobile phones and PDAs. They have limited resources and up to 16-bit displays. Current image/video coding systems can hardly manage this case effectively. To enhance coding efficiency on this condition, a reversible color transform customized for hicolor systems is derived from Y'CrCb and JPEG2000 Reversible Component Transformation (RCT). The transform proves simple but highly-decorrelating, and able to reduce the computation time of decoding. Comparison experiment demonstrates the effectiveness of this transform with equal or even higher coding efficiency on low-end devices with 16-bit display mode.