Indeed, paper maps are alive and well in the field of hiking/camping. It is a terrible experience trying to navigate even on the biggest of phone screens. Even the stuff one can print at home is, maybe, on an A3 sheet of paper, hopefully in colour. A vast improvement over the phone, and still not unwieldy. But to me, nothing compares to those huge mapsheets that fold accordion style. You can take in SO much more of your terrain and locate yourself so much better in your surroundings.

One of my favourite things to do while out hiking is to sit with a compass and a map and try to identify peaks and glaciers. I could do it for hours.

ETA: Everything I've heard about CalTopo makes it sound like God's gift to us.