Abstract: Mobile communications devices are described. In an implementation, a mobile communications device includes a first housing that is approximately square and that includes a display device. The mobile communications device also includes a second housing that is approximately square, includes a keyboard and is rotatable with respect to the first housing at respective corners of the first and second housing. The second housing is rotatable with respect to the first housing between a first configuration in which the first housing substantially covers the second housing such that the keyboard is covered and a second configuration in which the keyboard is exposed.