I may just be being a luddite but there are 3 or 4 cards I like to have with me along with a little cash. I go back and forth whether it's worth carrying an actual wallet or not. I don't want to be in a situation where, if something happens to my phone (including running out of juice), that I have absolutely nothing else on me.

(I also print out airline boarding passes unless it's not convenient to do so for some reason. I'm not fanatical about it, but if it's just 30 seconds of effort, I figure that I might as well.)