You read that right. A file manager. You asked for file management on Windows Phone 8; you got it.
Aerize Explorer is a utility app lets you manage files and folders on your device and external storage. You can cut, copy and paste files. You can move, delete and rename both files and folders. There is a search function too to help you find your files. The app also lets you share files and folders to any application that accepts files as a sharing target. You can also share files with other devices via NFC, Bluetooth, Email, and other media.
You can check file properties, as well as open files that have associated apps installed.
I have had Aerize Explorer installed on Big Red for about a week now, and using it has been nice and without hassles. If you want full access to manage your files and folders on your Windows Phone smartphone, you cannot go wrong with Aerize Explorer. Highly recommended.
Download: Aerize Explorer