I am a student so I would use this for moving files, downloading readings, reading PDFs, my printer is not wireless, email, I also own a small business and I would use the square on it too. (the square is a little device that allows me to use credit cards at the farmer's market, to charge people for my product)
I have a Sony Vaio laptop and an HTC droid phone. I don't think I would be writing 15 page research papers on it, but you never know.
I do like to read for pleasure so I would use it to download books as well.
Thoughts, opinions, the good, the bad and the ugly.
I don't think the square card reader would work on the nook. Quick research (I'm not really digging or delving just glancing at results) says no on the kindle fire, too. Looks like you need a microphone input jack which neither have?