With the iPad Camera Connection Kit allowing users to connect a variety of unexpected USB devices (like a MIDI keyboard) to their iPads, the next logical question was, "Is there something similar for Android?"
Although it's not advertised or sold by any of the big Android phone manufacturers, the solution is a cheap cable called a USB On-The-Go adapter.
USB On-The-Go (Amazon link), or USB OTG, is essentially a female USB port that plugs into the Micro-USB port of a phone or tablet, allowing you to connect devices that use a standard USB 2.0 or 3.0 connection. In a nutshell, the adapter allows the Android device to be a "USB host," powering and communicating with the connected device.
So far, it's been difficult to figure out which Android devices are compatible with the USB OTG cable. It's clear, however, that the Samsung family of Android phones and tablets are the most USB-friendly of them all, allowing users to connect the greatest variety of USB devices.
Even though USB host mode is technically available in devices running Android 3.1 and above, the hardware manufacturers (OEMs) must enable the feature. And, even then, the OEM might limit the types of USB devices the Android phone or tablet supports.
With the help of this crowdsourced chart, and some of our own testing, we found that the following devices are compatible with USB OTG:
Samsung Galaxy S II (S3)
Samsung Galaxy S III (S3)
Galaxy Nexus 7*
Samsung Galaxy Tab
Acer Iconia Tab A200
Acer Iconia Tab A500
Notion Ink Adam
Toshiba Excite 10
Sony Tablet S
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