most functions are “advanced” and cost extra

To get all of the functions, be willing to spend an extra $10 over and above the initial purchase price (or $10 total if a demo). The app causes damage to the core files within OS X as it is OVERLY aggressive in cleaning those files. I would not buy again and do NOT recommend this app to anyone. Cocktail is a much better choice. Be sure to perform a FULL backup to time machine or super duper, and be willing to spend the hours it takes restoring your system. However, if you have advanced to El Capitan and your backups are of Yosemite, be ready for an all night restoring session. YOU HAVE BEEN WARNED!

Stu Q. about iBoostUp