@AdrianT_2471969 Some cruise ships offer a fairly decent wifi speed - it depends on the cruise line.
If the wifi is half decent, you can speak to people using an App like WhatApp - we have done this on a number of occasions. Also, your phone will work over EU networks using your Smarty plan (up to 12Gb of data over EU Roaming) - this operates once you are either in or very near to ports.
