These apps require you to have a root enabled device, if you don't know what root is your most likely don't have it & I don't recommend rooting unless you really know how! Please remember with any root required app caution is always recommended!
Another app I feel is required if you are rooted. Having the latest version of Busybox will mean that Root apps will run at there best and this app does just that, it keeps your BusyBox updated to the latest and greatest version.
Not really an app for everyone but anyone on Android 4.4 (KitKat) I recommend this because as you may already know Android 4.4 KitKat removes the ability to write files to the MicroSD card and this app fixes that.
This is basically a simplified version of SD Maid for those users who want to rid their device of unnecessary files but don't quite have the advanced know-how required when using SD Maid. As with any root app use with caution!
This doesn't really require root but if you have root it opens up some great additional features & not to mention this is in my highly recommend list: http://playboard.me/channel/5012cdc44fbd8c436a000000/fhl09-s-highly-recommended
Another example of great use of root permissions, no longer do you have to freeze apps only to unfreeze them later when you want to use them, put them into hibernation instead. The app remains but won't run in the background using precious resources.