What Is USB OTG? (And What Is It Used For?)

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Connecting your favorite USB gadgets to a computer is simple, thanks to the availability of multiple USB ports. However, if you want to use those same devices with your phone or tablet, you'll need to use a USB OTG (On-The-Go) adapter or cable. These adapters usually have a micro USB or USB Type-C connector on one end and a USB Type-A port on the other. You simply need to plug the adapter into your phone, tablet, or other compatible devices, and start using various USB-powered gadgets. 

When you plug a USB device into a computer, the computer acts as a host while the connected device functions as a peripheral. However, a USB OTG allows both devices to switch these roles as needed. For instance, when you use a USB OTG adapter to connect a flash drive to your phone, the phone acts as the host. Conversely, when you connect your phone to a PC using USB OTG, the PC becomes the host, and the phone acts as a peripheral. 

USB OTG devices typically cost between $5 and $10, and you'll come across various options when shopping for one. You can choose an OTG adapter for a compact solution or an OTG cable for added flexibility. The adapter's port may be USB 2.0, 3.0, or higher, and some models even feature multiple ports for functions like pass-through charging. 

With a USB OTG adapter, you can connect a variety of USB devices to your phone or tablet. For instance, you can use it to connect a flash drive or external hard drive to transfer files, which is especially useful if your Android or iPhone has limited internal storage. You can also connect your device directly to the camera to transfer photos without needing a PC. Further, with an app like DSLR Controller, you can even control the DSLR camera using your phone or tablet. 

USB OTG also makes it possible to connect a wired keyboard and mouse to your phone or tablet. This is ideal if you want to have a desktop-like experience on your Android or iOS device. Additionally, you can use it to connect a printer to your phone, so you don't necessarily need a Wi-Fi printer to print from your smartphone. 

If you are into gaming, USB OTG lets you connect a USB gaming controller to your phone. With this setup, you'll be able to play supported games using the controller. It's also useful for content creators, as it allows you to connect USB microphones for high-quality audio recording. Similarly, the USB OTG supports several other plug-and-play USB devices, including MIDI-compatible musical instruments. 

Most modern smartphones and tablets support USB OTG, but you can check your device's user manual to confirm compatibility. If you have an Android device, you can also download the USB OTG Checker app from the Play Store and run it to verify support. 

Connecting devices via USB OTG is fairly straightforward. You simply need to plug the USB OTG adapter into your phone or tablet's charging port, then connect the other device into the adapter's USB-A port. Once connected, your device will automatically recognize it. However, on some phones, the OTG feature may be disabled due to security reasons. In such cases, you'll need to head to the Settings app, search for "OTG," and enable the toggle.

On iOS devices, you don't need to change any settings to use OTG devices, but compatibility is limited to a handful of devices, such as external storage devices. Even then, you'll need to format the storage device in a supported file system, like FAT32 or exFAT, for iPhones and iPads to recognize it.