Even though using GoGo for DL "stuff" is supposed to be free, often times it doesn't seem to work that way.

Once, recently, I did an online chat with GoGo customer service to complain, and they gave me a 30 minute pass, and my app worked PERFECTLY!

Of course, that doesn't address the fact that, it's supposed to work for the whole flight - and, this might be a PIA to do on a short flight just to use a drink coupon.