How does this flash drive phone interface work?

Factual Questions
1

I bought my buddy a high-capacity thumb drive for Christmas. I didn’t notice when I bought it, but the non-USB end had a cap underneath which is a plug that fits into a standard cellphone. How do you use this? Plugging it into a phone doesn’t bring up a window or anything.

2

It sounds like a SanDisk Dual Drive

3

Hit wrong spot on my phone.

On my android phone I can plug it in and the app starts up. It’s useful to move files from phone to pc. Or just from phone to dual drive. There’s a SanDisk memory zone app in the play store. I must have installed that app.

4

I have a few of these. The micro USB connector will go into the phone/tablet data/power micro USB data connecter and allow you to transfer data back and forth the same way you do with a flash drive for a standard PC USB slot.

5

Okay, we found the apps. Turns out you need a mounter for the drive, and a file explorer, but they’re both free.

Thanks all!