As mobile devices that can accommodate multimedia services are increasingly used, video data transmission consumes a significant amount of wireless channel bandwidth. On the other hand, the sizes and resolutions of mobile devices show large variations. In this paper, we investigate the optimal transmission of video data depending on the size and resolution of the mobile devices that include smartphones, tablets and notebooks. A series of subjective tests indicates the bandwidth consumption for multimedia services can be significantly reduced by considering the size and resolution of displays and content characteristics.