There is not any magic always-works-best-solution to routing. Different phone apps and some GPS options vary from one situation to the next because they are all designed for a generic system of roads and generic systems of databases for road data. Thus what works best one day might not be the best option the next day. Several months ago I wrote up a lengthy post on how I do my day to day routing on a several week long tour. Described how I use paper maps, GPS, and phone apps. Bottom line, some days the paper map was the best option for routing. That post is at:
https://www.bikeforums.net/21179305-post2.html