In Ubuntu Software there are duplicates listed for some applications like: Calendar; GNOME Software; ImageMagick; Online Accounts; Software & Updates; UXTerm/XTerm.
I believe they should not be listed twice as most other applications aren't.
My system is a fresh install of Ubuntu 17.04. Is there a good reason for this issue with Ubuntu and does anyone else encounter it?
sudo apt update
then check it again. – Ravexina Jun 18 '17 at 20:14