"Cleaning up RAM" is counter-productive. The way all *nix-based operating systems work is on the basis of "empty RAM is wasted RAM", so what they do is leave recently or frequently used apps inactive in RAM. If the OS actually needs that space for something else it will clear it. Otherwise when you next use the app it is there already, and not having to reload it from storage is both faster and uses less power. Apps like Clean Master live off a myth, based on the way that older versions of Windows used to work, that it's a good thing to have a lot of free RAM, but what clearing RAM actually does is waste energy. Also they interfere with the operating system's own attempts to learn your usage and optimise the system. There are many discussions of these type of apps on the web and in this forum: they go under many names (task-killers, RAM-boosters, battery-boosters, you name it), but they are all the same snake oil.
