The problem with this this sort of thread, is that almost immediately it will descend into a mobile / camera stand off - or to put it another way photographer / happy snapper standoff, and l suppose l am guilty of doing that, but at least l can plead that Craig inadvertently started it off first.
If you are a serious photographer, your equipment of first choice, most certainly is not a mobile. Why - simply because of the lack of control, taken away from you the photographer by the software imposed upon you by the mobile manufacturer. Yes you will achieve very acceptable images from mobiles, but they are not yours - you may have pointed the mobile in the right direction, but thereafter it is the in-built software that decides all most everything else. Now if that is your thing, and you are happy with the end result, then great ( and l really mean that ) for at the end of the day the only person who really has to be pleased by what they take is the taker.
However, if you are from the other standpoint, and you wish to be in control of your final image, you wish to control such things as depth of field etc, then mobiles are not the way to go fro you, and thus you will need something to carry your equipment in, which leads us nicely back to what in reality this thread is really about, i.e.: a camera bag.