I do usually carry a paper map and compass if I'm somewhere I don't know well. I have broken a phone and had the battery die and am very aware that I'm a dropped phone away from being utterly and completely lost.
The only times I have made significant route finding mistakes in the last ten years were after I started using a GPS for route finding - in both cases I took the wrong ridge down from a peak. My wife was also in a group that managed to descend completely the wrong side of a mountain the first time the person leading used a GPS...
