Sinder HD is a nice iPhone theme designed for Retina devices (4.2.1)
Sinder HD is all Stock themed, includes Auto theming appstore icons (enable Summerboard mode for these), Custom wallpaper is in the theme folder (will need to be applied through iTunes).
To apply FolderSwitcherBG you need to delete the `FolderSwitcherLinen0` to `3` in var/mobile/Library/Caches.