For multi-hour and day hikes I usually use the combination of maps.me, park pamphlet, and photos of large posters near the trailhead. Works reasonably well, although I realize that may not work in a multi-day backcountry, mainly due to the battery and reliability issues. Haven’t done those in a while but that totally would be a trip where I would pack ye olde compass, paper map, additional external phone battery and would check phone or GPS only once in a while to make sure I am not off route.