USB OTG File Manager

USB OTG File Manager app lets you to read USB flash drives as well as card readers
Now there is no need to find PC for backup your important files pesent in your phone. You can back up by directly connecting pen drive to your phone and copy the contents.
USB OTG File Manager app lets you to read USB flash drives as well as card readers from your phone or tablets. All you have to do is connect the flash drive to an OTG (On-the-go) cable then open this app you will see all files in USB drive and you can open them.
This application has been designed for Nexus products which have an USB "OnTheGo" port, as the Nexus 5, Nexus 7 and Nexus 10, and the brand new Nexus 6 and Nexus 9. But it could work on any device with an USB OTG port Under Android 4.0 or later, including the last Android 5.0 Lollipop.
For now, FAT32 filesystem is supported for data read and write, and NTFS filesystem is only supported for data read. You can use USB sticks or SD card readers with any compatible USB OTG cable.
Root privileges are NOT necessary!
Easy to access OTG devices through OTG File Explorer application. The application will launch on attaching OTG device to your mobile. 
There are various OTG (On The Go) devices available in the market like OTG Pen-drive, Flash drives, Pen drives, Mic, Keyboard, Digital camera or Keyboard etc.
USB OTG File Manager for android allows you to open and copy files from any USB mass storage device with a FAT32 or NTFS file system using the USB OTG port of your device, tablet or phone.
OTG File Explorer FEATURE
Audios:- You can manage all music and sound related files. (Supported file formats: mp3, ogg, flac, m4p, wav, wma and etc).
Videos:- You can manage all video files in your device. (Supported file formats: asf, avi, flv, mp4, mpeg, wmv and etc).
File Browser:- OTG File Explorer helps you manage all your files efficiently! With an intuitive interface, File Manager allows you to handle any file or folder whether they are stored in your device, microSD card, or cloud storage accounts.
Application:- OTG File Explorer support application management like Uninstall applications, delete application and manage application like system app and user install app.
File Transfer:- OTG File Explorer support connect applications to Computer and You can access remote or shared storage like NAS and FTP server.
Images:- You can manage image and picture files in your storage. Image preview is available. (Supported file formats: bmp, gif, jpg, png and etc).
Documents:- You can manage all document files in your device. (Supported file formats: doc, ppt, pdf, and etc).