1) Camera: iPhones are about the best lightweight camera I’m willing to purchase 2) Navigation: Offline maps with details like slope angle are critical when traveling in the backcountry in winter. Yes I use paper maps too, but some things are much easier digital. 3) I don’t want to leave it in the car to get stolen.
And about airplane mode. Yes “disconnecting is a choice”, but if the internet is just the flip of a button away, I’ve found I’m not able to keep that button off.