They're actually custom wallpapers overlaid with nicolai's desktop switcher, so they're not actually icons. Any time I tap on one of the "icons", it'll take me to the appropriate homescreen (the blue indicates which homescreen is currently selected) using the desktop switcher. The bottom battery indicator is a Queen Beecon widget with a custom battery icon that indicates the % battery remaining. I'm also using nicolai's calendar home desktop widget as my calendar.