If in case you have downloaded an app on your Mac system from the internet or from a disk, it can be removed easily by using the following method. Way 1: Delete Applications on Mac with App Uninstaller Cannot Delete Some Apps on Mac? What to Do.Way 4: Completely Uninstall Application on Mac and Leftover Files (Recommended).NOTE: Leftover Files and Bundling Programs.Way 3: Uninstall Purchased Apps using Launchpad.