OTG Cable
What is an OTG?
USB OTG Cable is the short form of USB On The Go Cable, Which Really Helps you to Transfer Files

From a Flash Drive or SD Card into Your Phone Without Connecting The Phone into a Computer,
Also, You can Transfer Files From Your Phone into a Flash Drive or SD Card. OTG is not using only for
Transferring files, You can add additional hardware such as storage, keyboards and musical instruments.
if Your Device OTG Supported then this logo will be visible in the packaging
An OTG cable has a micro-A plug on one end, and a micro-B plug on the other end
(it cannot have two plugs of the same type). OTG adds a fifth pin to the standard USB connector,
called the ID-pin; the micro-A plug has the ID pin grounded, while the ID in the micro-B plug is floating.
A device with a micro-A plug inserted becomes an OTG A-device, and a device with a micro-B plug inserted becomes a B-device.
The type of plug inserted is detected by the state of the pin ID.
How to use OTG Cable?
if your Device OTG Compatible, Then simply connect the Micro USB into your Device and plug
the Pen-drive into another side USB 2.0 Port, Phone will prompt file manager automatically
Use of USB OTG allows those devices to switch back and forth between the roles of host and device.
For instance, a mobile phone may read from removable media as the host device, but present itself
as a USB Mass Storage Device when connected to a host computer.
Some devices can use their USB ports to charge built-in batteries, while other devices can detect a
dedicated charger and draw more than 500 mA (0.5 A), allowing them to charge more rapidly.
OTG devices are allowed to use either option
Where to Buy Original OTG Cable & Adaptor?