The purpose of the GPU (Graphics Processing Unit) is to speed up the production of images from a frame buffer that is meant to be displayed to a display.
GPUs are often more efficient than general-purpose CPUs for techniques that need concurrent processing of big data blocks. They are also particularly good at editing computer visuals.
These days, cellphones come with sophisticated integrated chipsets that, depending on how they are programmed, may perform a wide range of functions. These chipsets would not function without their GPUs, and as mobile games push the limits of hardware, GPU performance is becoming more and more crucial.
