What is OTG ?

〝USB On-The-Go〞 often abbreviated to USB OTG or just OTG, is a specification first used in late 2001, that allows USB devices such as digital audio players or mobile phones to act as a host, allowing other USB devices like a USB flash drive, digital camera, mouse, or keyboard to be attached to them. Use of USB OTG allows these devices to switch back and forth between the roles of host and client devices. For instance, a mobile phone may read from removable media as the host device, or present itself as a USB Mass Storage Device when connected to a host computer.

In other words, USB On-The-Go introduces the concept that a device can perform both the master and slave roles – whenever two USB devices are connected and one of them is a USB On-The-Go device, they establish a communications link. Whichever device controls that link is called the master or host, while the other is called the slave or peripheral.

What can OTG  be used for ?

Having OTG support on any phone / tablet is great, but it really comes in to its own on phone / tablet with no SD card slot and limited on-board storage. In this case a USB thumb drive can be connected to yourphone (via a special OTG cable) allowing you to browse the thumb drive and move files to and from your phone / tablet (you may also need to download file manager app). In addition to thumb drives you can also connect to SD card readers, cameras, and even external hard-drives.

Moving files and adding storage aren’t the only way OTG can be used, you can even connect a mouse or keyboard to your device allowing you to be more productive on the go. This is especially useful for Android tablets.