Yes, and it is the one piece of prep worth actually doing.
Download the app and build your group at home, on a normal connection. It takes a couple of minutes. Leave it until the terminal and you are fighting several thousand other people for the same bar of signal, at the precise moment everyone is trying to download boarding passes.
Get the others set up too, not just yourself. A group with one person in it does nothing at all.
Once you are aboard there is nothing to configure. It finds other phones by itself — no pairing, no codes, no settings.
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