The UI is native to Linux based Operating Systems using a GTK based Desktop Environment (Gnome Shell, Ubuntu Unity and a few others). Honestly, I've used both

The UI is native to Linux based Operating Systems using a GTK based Desktop Environment (Gnome Shell, Ubuntu Unity and a few others). Honestly, I've used both for about as long as each other, I find both to be equally annoying to use. Much prefer to use Inkscape or Fireworks, but fireworks doesn't come installable as a Deb and doesn't work natively on a Linux based Operating System so I don't care for it.