Is that UK good manners you're observing, or your personal good manners? Where I live in the US, east coast mid-Atlantic region, everyone seems to always have their smart phones out and checking them, whether at meetings or dinner or social events. I don't see people doing that as much down south, so even in the US smart phone etiquette might vary by region. West coast manners seemed the same as my area, but I'm never there long enough to be certain.
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