What is USB OTG?

USB OTG stands for ‘USB On-The-Go’. Basically, USB OTG is a way of connecting USB accessories to smartphones and tablets which don’t have full-size USB ports. These accessories could be USB flash drives, card readers, keyboards, mice or gamepads. There are also some advanced tricks you can pull with USB OTG – more on these later!

What do I need for USB OTG?

Because microUSB and USB are different connectors, you’ll need an adapter which translates one to the other. These USB OTG cables are quite simple, and usually look like just a full size USB connector and a micro USB connector with a short cable connecting them. Here’s one example of a well-rated USB OTG adapter.

Here are device-specific USB OTG cables for some phones: Galaxy S5, Galaxy S4, Note 3, Note 2, Xperia Z2

What other kinds of USB OTG accessories are there?

You can also get USB OTG adapters baked into other connection kits; essentially translating a micro USB connection into full size USB as well as HDMI, microSD cards and other useful connectors.  Here’s an example of a Connection Kit with USB OTG.

Finally, there are also some USB flash drives with microUSB connectors, designed to be used partially or exclusively with mobile devices. If they work on computers as well, you’ll usually find a full size USB connector on the opposite side. Here’s an example of a USB flash drive with a microSD connector.

 

Clockwise from left: USB OTG adapter, connection kit with USB OTG, microUSB flash drive

What devices support USB OTG?

Most modern Android devices (running version 3.1 or later) support USB OTG. You can see if your device supports USB OTG with apps like USB Host Diagnostics, available on the Google Play store. Note that you’ll need a USB OTG cable and a USB device in order to run the test.

USB OTG is also available for Windows 8 and BlackBerry 10.2.1 devices with microUSB ports. Unfortunately, USB OTG is not supported on iOS or Windows Phone.

Do all USB accessories work with USB OTG?

Not all USB accessories work with USB OTG. Some USB accessories draw more power than OTG can provide; e.g. a gaming keyboard with LEDs turned on. Your mobile device will also need to support the USB device you have connected, so more esoteric accessories that require special software on Windows or Mac won’t likely work.

Do I need an app for USB OTG?

It depends. Some Android devices require an app to see the contents of USB drives or SD cards connected via OTG. The Nexus Media Importer and USB OTG Helper are two working examples. Note that some apps may require root.

What else can I do with USB OTG?

USB OTG can also be useful for charging phones from tablets. Tablets generally have much bigger batteries than phones, so you can use them as portable chargers. Just connect a USB OTG adapter to the tablet’s microUSB port, then plug your standard microUSB charging cable into the phone and connect it to the USB OTG adapter. You could also do this from phone to phone, but this is less commonly useful.

I have another question!

Sure. Let us know in the comments below or on Twitter @mobilefun, and we’ll answer your question.