Many of my members have both a mobile device and a laptop. So I set up two styles, the Default Style and a Mobile Style. Currently the Xenforo software records the members current style in the xf_user table. So every time a member switches between their mobile device and their laptop, they have to select the appropriate style. This is a PITA as many members will need to do this dozens of times during the day. I suggest a cookie based style setting. This way the style the member uses for his particular device stays with the device in the form of a cookie.