I have to check in with my students, make sure assignments are opening and closing and just be available for them even while on the cruise. Carny has 3 levels of Internet, I do not take my own laptop, I just use the computers onboard. It does take time for it to process, so I would not recommend any of my students taking a test while on the ships internet. It also loses connection when the ship leaves port, experienced that last fall while trying to answer a students email. The Internet Café is in the Atrium, so I had plenty to watch (and drink since I had the CHEERS package that cruise due to how we situated everyone over 2 cabins) and did not notice how long it took to really connect, but I remember thinking, "I could quite possibly run a message over to the mainland before this sucker loads".
I have not tried FaceTime, ETC, I am like you, I really could care less about Angry Bird Tournaments, billiards online or even Facebook while I am on a cruise. I have a strict no posting rule for our family so as not to publish when we are not in town.
We purchased the $16 a day plan so I could access my classes easier, one of the boys did use his smartphone to the wireless package every second I was not using it for classes. He was told that if he ran up our cellphone bill, he would be opening up his bank account to pay for it. He set it up correctly in airplane mode. Still, I would not hook my phone up, I want to unplug as much as possible during my cruise.
Hope this helps in some small way.