It’s no secret that Mac OS X doesn’t always make it easy to completely delete an application from your system. There are preference files littered all over the hard drive, and most apps not offering an uninstaller, it’s a real pain in the behind. Even apps that offer an uninstaller inexplicably don’t always delete all the files. While there is no foolproof way of removing ALL those files, AppCleaner goes a long way in making the task easier. AppCleaner is a free utility from FreeMacSoft that like other app-remover applications like AppZapper, removes applications and their supporting files. Unlike AppZapper though, AppCleaner offers the option of running in the background – meaning you don’t have to remember to use it. 
The SmartDelete preference option in AppCleaner sets your system to automatically gather all the files attached to a particular application when you drag that app to the trash. You can then selectively decide if you want to delete all or some of the related files along with the application itself. You can also protect your preferred applications from accidentally being deleted if you so choose; a nice little safety valve. I used AppZapper for quite a long time until I came across AppCleaner a few years ago. I’ve been using it ever since with no problems whatsoever. As I stated earlier, no app uninstaller is perfect. But AppCleaner is the best I’ve used at finding all the files associated with an app. And I love that it does it automatically. AppCleaner is free, runs in Mac OS X 10.4 through 10.6.1.
