Ferromagnetic user interfaces are described. In embodiments, user interface devices are described that can detect the location of movement on a user-touchable portion by sensing movement of a ferromagnetic material. In some embodiments sensors are arranged in a two dimensional array, and the user interface device can determine the location of the movement in a plane substantially parallel to the two-dimensional array and the acceleration of movement substantially perpendicular to the two-dimensional array. In other embodiments, user interface devices are described that can cause a raised surface region to be formed on a ferrofluid layer of a user-touchable portion, which is detectable by the touch of a user. Embodiments describe how the raised surface region can be moved on the ferrofluid layer. Embodiments also describe how the raised surface region can be caused to vibrate.