Communication

On Board
For keeping in touch on board the boat you should find "Wave Phones" in your stateroom. These can be used for making and recieving calls and texting on board the ship. They only work contacting other Wave Phones. You do have to sign a damage waiver before using them (usually at check in) and a charge of $250 is incurred for loss of damage.

Alternatively the Disney Cruise Line Navigator app on Apple devices allows free texting between devices using the app while onboard the ship. The app is also provides deck plans, event and activity listings (like you get in your daily Navigator). You should download the app before leaving home if you want to use it. The app makes use of the wi-fi network on board the ship which is free only for use of the app.

Internet
Theoretically all staterooms have wi-fi access as do most lounges. In practice due to the construction of the boat the signal varies hugely from stateroom to stateroom. As the bandwith is governed by it going via you will also find it becoming sluggish during peak usage times such as mid afternoon. Recently Disney have switched from time based charging to data based charging. Current costs are: It is important to note that you cannot upgrade from up package to another. So if you buy Small then decide you really need Medium you will have to finish your Small and then buy the Medium in addition.

Your package can be used on all of your mobile devices and once you reach the limit of the package size you should be cut off until you choose your next package (except Pay-As-You-Go where the charges continue to rack up with no ceiling).

To make sure that you do not use your package faster than you intend make sure you turn off automatic updates for apps (including location services) and automatic downloads of mail. You should also turn off wi-fi every time you finish using it.

Any unused data is forfeit, no refunds are made.

If you do not intend to use the Internet, or to avoid any data charges on your phone bill make sure you turn off mobile data on your phone.

The ship also has an internet café which charges for internet usage at the same charge as wi-fi.

Mobile Phones
As a side note in most cases mobile phone calls while you travel will be very expensive, when you can get a signal at all which will likely only be when you are in port or sight or land. Disney, like many cruise lines, does provide the Cellular at Sea service which provides a mobile phone network that can be accessed by almost all mobile phone carriers. You phone will likely automatically connect to it if not switched off or in airport mode and if you have any sort of data sycing will continue to sync as normal. Cellular at Sea charges are exceedingly expensive, currently a minimum of $3.00 per minute for phone calls and $0.02 per Kb (around $20 per Mb) for data.