Removing non App Store apps
To remove just the app you can drag it to the trash, use ⌘ cmd+⌫ backspace, or right-click → Move to Trash the app.
To remove the app, its preference files, and other related files, you will need another app along the lines of the free AppCleaner application.
Here is a Lifehacker article titled "The Best App Uninstaller for Mac", which chose AppCleaner as the best uninstaller for the Mac (in 2011).
There isn't an app out there which really deletes all of the files related to a certain app. To be completely sure, you have to do it by hand.
- Open up the Terminal
- Type in
sudo find / -iname "*YOURAPPNAME*" -print > ~/Desktop/uninstall.txt - Open the uninstall.txt file at your Desktop and look at the content
- Now go through, line by line, and when you are sure a path is related to your app, type this on the command line (the path is just an example here):
sudo rm -r "~/Library/Application\ Support/APPNAME"
Many apps don't look deep enough, or in favor of security, don't delete all files they find.