USB OTG (USB On The Go) is a standard that enables mobile devices to talk to one another. Traditionally mobile devices could only connect to a Mac/PC by USB, but USB OTG makes it possible for devices to connect directly to each other. And that's not all USB OTG can do. By enabling your device to act as a USB host – that is, to be the boss of other devices that you connect to it – you can use additional hardware such as storage, keyboards or even musical instruments together with your handset.