Stabilizing element for use on mobile devices

The stabilizing fin includes an upper vertical stabilizer element, a hollow tubular element, and a lower vertical stabilizer element. The upper vertical stabilizer element has an upper end for attachment to a bottom surface of a water planing device. The hollow tubular element has an upper portion depending from a lower end of the upper vertical stabilizer element. The tubular element has an open front end and an open rear end. The lower vertical stabilizer element has an upper end depending from a lower portion of the hollow tubular element. During use thereof the upper and lower vertical stabilizer elements provide lateral stability and the hollow tubular element provides increased lateral stability and vertical stability for enhanced control by a user. The water planing device maybe, for example, a surfboard or a wind surfing board.