You might just want to use the ships wifi. Make sure you turn your mobile band off and only connect the the wifi when you really want to use it. You don't want to get hit for data fees anytime an app goes polling for updates.
A Bad Day At Sea [with power] Always Beats A Good Day At Work
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014