Note you cannot make edits without root access. This is a jailbroken application and does not work to its full extent without a jailbreak. Installing iFile here in no way gives you a jailbreak. This is also a free version see that the paid version is $4. So this version will not register. What follows is the Cydia description.
iFile is a complete file manager and viewer running under root, iFile gives you full access to your jailbroken device's files, like Finder does on your desktop Mac. iFile is your tool for advanced management and customization of files on your device,