Getting your group set up before you sail
Install and pair while you still have a normal internet connection. Doing it at the terminal is how it goes wrong.
Do this at home, not in the terminal queue.
Everyone in your group installs the app and sets up their account while they still have ordinary internet. Pair with each other then too. The first setup is the one part that is easier with a connection, and embarkation day is exactly when the terminal WiFi is at its worst and everyone is tired.
Once you are paired, you do not need a connection again for messaging between your phones.
Worth doing at the same time: agree a couple of habits. A message that has not arrived yet is not a message that failed — on a quiet ship it may be waiting for somebody to walk past. Agree where you will meet if you cannot reach each other, the same way you would have before phones existed.
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