An example image display apparatus includes processing circuitry such as a communication processor and a game processor. The processing circuitry continuously processes a communication-related function and selectively processes a game-related function. When the game function is in an off-state, binary image data and color image data for the communication-related function are written to a first memory and to a second memory, respectively. When the game function is set to an on-state, color image data for the game-related function is written to the second frame memory instead of the color image data for the communication-related function. A display includes a composite image based on the binary image data stored in the first memory and the color image data stored in the second memory.