ZUGate

Works fine, my only issues are that 1) I cannot move files from my USB to my phone or vice versa, I'd still have to connect both to a PC. 2) I cannot view files that are zipped, meaning, again, I would have to plug the USB/Phone into a PC and unzip the files first. 3) It takes upwards of 5 minutes for files to load. I thought this was due to how large of a USB I was trying (100gb+) but even trying a USB with only 5mb worth of files on it takes 5+ minutes to load too.

This app not only allows me to copy to/from NTFS & exFAT volumes (on devices that lack support for these file systems), it also mounts these volumes so other apps (Opera, Files by Google, various downloaders, etc) can write to them. Also it can create/manage encrypted folders. Oddly the app's integration with Playstore payment services is broken. Let me know when it's fixed; I want to donate.

great app, and free. excellent for power cuts so I can plug a USB drive into my phone to watch movies etc. unfortunately the videos always freeze, usually after only a few seconds. if I copy them to the phones internal storage or SD card they play fine though.