The Sony Ericsson XPERIA X1 is a Windows smartphone released at the end of 2008. It has a sliding QWERTY keyboard. The XPERIA X1 is the first Sony Ericsson phone to use Windows Mobile. The phone was designed and built by HTC, though sold through Sony. The X1 comes with Opera Mobile pre-installed. The Sony Ericsson XPERIA X1 contains nine different options for the homescreen panel, allowing some customization for how they want their homescreen to appear. More panels can be downloaded from Sony Ericsson.