Portrait, is a lot closer of a shot, so you need to hold the phone farther from the object, and the photo is a farther away shot so you need to hold it closer. Portrait you can’t zoom in, photo you can.
portrait, when your focusing on an object the phone will tell you if you are too close, if it is, then move the camera away. When you are in portrait, it focussed on one thing, and blurs out the back ground, and it has different settings, where itll black everything out except the object you are focussing on.
the portrait gets some really nice photos! (Once a person figures it out lol)