Using some of the changes from #3133, we can add two new segments, isMobile & isDesktop. They would have to be views that are transformed into existing segments, ie, isMobile -> operatingSystem==ios,operatingSystem==psp,etc. . This isn't currently done and it may take some work to make it possible.
Could be done around:
Index: Segment.php =================================================================== --- Segment.php (revision 6368) +++ Segment.php (working copy) @@ -104,6 +104,8 @@ $sqlName = $segment['sqlSegment']; + // somewhere here we could read a 'viewSegment' and use this instead of a segment meaning a SQL field + // check permission if(isset($segment['permission']) && $segment['permission'] != 1)