For a few days, I’ve installed CleanMyMac on my computer. This software is meant to help me freeing as much of my hard disk space as possible. Therefore I can scan my disk for double files, huge (forgotten) files, junk files, temporary files, caches and unneeded audio files needed to support all the other languages beside mine.
It can also help me uninstalling applications. When uninstalling apps manually, always some files remain. Often these are located in my home, in hidden registry files or even in hidden folders (i.e. settings or registrations). CleanMyMac scans the app before uninstalling it to find all those remains and offers to delete them too.
CleanMyMac resides in the bar on top of the screen and watches some internals of my computer (network speed, ram usage, free disk space) and offers help whenever the recycler is too full, an app hangs or so.
The OS also has a good mechanism, to kill hanging apps. So, this feature is kind of useless. There are also some other apps available, that help to uninstall apps without leaving files on the disk. Deletion of i.e. languages files is (in my opinion) useless because they come back with the next update.
So, finding huge files and doublets is the main feature, besides seeing the size of the installed apps. You get an inside view of your hard disk and get the overview to decide which files to keep and which ones to delete
Secure deletion of files (= overwriting them first), searching for app-updates (even for those not from the Apple app store) and deletion of iOS-device backups from iTunes are really helpful. Decide, if you need it. Some of these features are not available otherwise. You could install the free trial and check it out on your own computer.