Review on 🔌 Powerful 3-Port Micro USB HUB Adaptor with OTG Host Cable - Compatible with Raspberry Pi, Android Devices, and More by Gary Stringfield

There is a switch on the right side. Putting it in OTG mode allows multiple USB devices to communicate with your device. By switching it to charging, you charge your device. For some devices, switching to charging disables the USB connection to the device. For some devices, switching to charging mode puts the hub into simultaneous mode, charging and granting access to the device. There are only a few devices that the hub explicitly supports in simultaneous mode. My Galaxy Note 3 is listed as supported for simultaneous mode and the hub is charging the device and accessing USB peripherals connected to the hub at the same time. Simultaneous mode also works on my 8 inch Acer Tab, although loading seems slow. Simultaneous mode doesn't work on my 10 inch Acer Tab. It also doesn't work on my 8 inch Nuvision Windows Tab. Otg worked on all devices. I deducted a star because the Amazon description didn't make it clear which devices were officially supported in simultaneous mode. This information is printed on the product packaging.