One of the greatest attractions of Sony Ericsson Xperia X1 - besides being the first Windows Mobile handset from the manufacturer - is the special user interface made of nine panels, for which dedicated developer tools are provided in order to expand it. Still, it seems that Sony Ericsson doesn't only support changing the panels, but even the whole UI. Spb Mobile Shell, available on the manufacturer's download site, is not a simple panel, but a completely new, alternative user interface that can be controlled easily with a finger at every point. The free user interface can be installed only on Sony Ericsson Xperia X1 and it is available for download at this link.