Pop OS uses a custom GNOME-based session with its own default settings and extensions. The default fonts are Fira Sans and Roboto Slab to match the Pop and System76 look. The Shell theme has a refined, consistent look that is somewhat flat while retaining light and shadow.The features of pop OS Ubuntu-based,Built from scratch,Nicely customized Gnome 3 as DE,Better support,No bloatware and much more.