Data charges are for anything other than phone calls or texts - browsing, you tube - sending or receiving photos or video.
International programs don't affect shipboard charges, though we did take a world phone with us to Europe to be able to check messages while in port.
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