Browser's Corner - as well as onboard WiFi there are a number of desktop internet browsing stations

See 2014 costs below which are the same for using WiFi on your own tablet

Internet on board the ship is very slow and intermittent and takes an age to log on which uses
up 2-3 minutes of your paid time. It is not reliably accessible from cabins
It might be better to go to bars and cafes ashore who provide free WiFi.
There is a bar next to the Cruise ShipTerminal at St Johns in Antigua which we have visited before.
I am sure that since outr last cruise in 2011, many more places will have WiFi