According to some embodiments, a mobile electronic device is provided with a linkage mechanism that couples first and second members of the device such that the device may be moved between a first position and a second position. The linkage mechanism includes a linkage intermediate the first and second members, the linkage having a fixed length. The linkage mechanism further includes a motion constraint mechanism that constrains movement of the first member with respect to the second member to a controlled motion. The linkage mechanism described herein may further provide that the top member rotates without increasing the length or width of the device.