Shape - The round mobile device (discs)

One advantage with a round all-in-one mobile device would be the ability to load media content from discs such as CD:s, DVD:s, Blu-ray etc. Just insert the disc into your device, and you're ready to consume the media content. Just like an ordinary portable CD player. I guess you could have a disc player in a rectangular device as well. But the round one would be optimal when it comes to minimization of a device's size.