For those who complain about being unable to delete files with this uninstaller (ironic, I know), realize that this is a limitation of any app in the Mac App Store. Apple forbids any app from making changes to files outside of its designated document folder in order to prevent viruses and malware from being installed on the Mac.
To bypass this limitation, you simply have to download a FREE app from the developers website which restores its full capability. This is the only way to sell ones apps in the Mac App store without crippling them or having to sell a second copy from the developers site. BBEdit, for example, has to sell a crippled version of BBEdit on the Mac App Store in order to meet the Mac App Store requirements for security, while it sells a full version on its site. Unfortunately, this is just the way of doing things since user security from malware has been emphasized.
Once the full features of the app are restored, TrashMe works wonderfully to uninstall applications and their related files. You can choose which files to remove. It also has additional features such as removing junk files from the hard drive.
It is much more full featured than the classic free app, AppCleaner, which is not sold in the MacApp store because it doesnt conform to the security limitations.
TrashMe is well worth its price. Thank you, TrashMe developer, Jean-Baptiste!