I have bought a Samsung 128GB USB 3.0 Flash Drive Duo in hopes of being able to use the Micro-USB side with my Sony XPeria Z3+. When plugging it in, I got no response or message from the phone. I tried looking up the reason why on google, but all i get are these responses on how to use a usb drive with the phone by using an OTG cable.
Is there any way that I can get the micro-usb side working on my phone? It must have been put on the drive for a reason, right?
In your case there is no need for an usb OTG cable. It does nothing else then wiring the USB Type A connector to the micro usb connector, there is no electronic involved. The same goes for the micro usb connector on the stick itself. It's directly wired to the type A connector.
Usually the device should recognise and mount the stick automatically although this can be different depending on the manufacturer. I assume that sony's android implementation does not mount it automatically, but they have a manual (thanks ernie for the link).
From Sony:
Find and tap Settings > Device connection > USB Connectivity > Detect USB device.
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