Along these lines, I admit with shame that lately I’ve been switching to airplane mode before looking up or modifying a contact, because it’s not obvious to me which combination of symbol-labelled buttons will do this without initiating a phone call. I feel old.
And don't get me started on trying to click on a missed call to either find out more about the number, access the voice mail or simply get rid of the "new notification" dot. I more often than not start calling the number although that's the last thing I want to do.