CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
Glary Utilities - The No. 1 Free, Powerful and All-in-one utility for cleaning your PC
AppCleaner - AppCleaner is a small application which allows you to thoroughly uninstall unwanted apps. Installing an application distributes many files throughout your System using space of your Hard Drive unnecessarily.
BleachBit - When your computer is getting full, BleachBit quickly frees disk space.
CleanMyMac X - Clean, protect and speed up your Mac
Clean Master - Some users swear by it, some call it a glorified snake oil that does more harm than good. That can be said about any snake oil, but what specific brand of snake oil can boast almost a billion downloads around the world?