Jim, can you give a crash course on how this works and how it could be beneficial for use with an iPad and 15000? 

  Also, if we invest in one, can it be used for other things on the IPad?

Like a test dummy, Jim crashes with this:

iUSBport 2 is essentially a USB port with WiFi. It can be used with a free app on the iPhone or iPad for file storage, photos, or even movies. There are two USB ports on the device. You can plug a USB stick into one and send data to it, or you can plug in two and copy from one to the other. There is also a hidden port that will accept an SD Memory card, which you can read or write to. It has its own battery, which you charge from a USB port. It's small enough for a pocket or purse, and in a pinch it could even provide a charge for your phone. Not bad for a device that's less than $100.