If you are looking for an alternative to iTunes or 25PP, then you must try SynciOS. It has been dubbed the best file manager for iphone by many iOS enthusiasts.
SynciOS can be used on iPhone, iPad, iPod Touch, iPad air and iPad mini.
SynciOS can perform all the tasks most file managers can perform and more. It can synchronize your media files (videos, music, e.t.c) to and from your iOS device and your computer as well as create backups for your iphone and restore when you need to.
There are other apps that have file manging functions like 25PP, iFunBox, Kuaiyong, iTunes e.t.c but SynciOS proves to be the most robust and easier to use.