To uninstall DropDMG, drag its application file to the trash. DropDMG’s data files are stored in the folder:
/Users/<username>/Library/Application Support/DropDMG/
or:
/Users/<username>/Library/Containers/com.c-command.DropDMG/Data/Library/Application Support/DropDMG/
You can uninstall the command-line tool by typing:
sudo rm /usr/bin/dropdmg
in Terminal. You can uninstall the manual by typing:
sudo rm /usr/share/man/man1/dropdmg.1
in Terminal.