CCleaner - CCleaner cleans, speeds up and frees up space on business endpoints.
CleanMyMac X - Clean, protect and speed up your Mac
Glary Utilities - The No. 1 Free, Powerful and All-in-one utility for cleaning your PC
AVG PC TuneUp - Peak performance for your PC. Keeps it going for longer. - More Speed Turbo Mode
Outbyte - Outbyte is a cmprehenmsive computer repair tool that is built to address a range of various system issues like clean up your drive, optimize performance and enhance privacy or security.
BleachBit - When your computer is getting full, BleachBit quickly frees disk space.