Alltrails, which we have used has one big flaw. In my opinion. It does not put an arrow or other direction marker on the map to show your direction of travel. This can be a real problem when you are out on the trail. I've been told by many taht Gaia GPS is better than Alltrails. Take a look at this article for other suggestions:
REI articleWhat ever you get download the map of the trail you are planning to take BEFORE you leave. You may well be out of cell phone signal range once you get out on the trail. Especially in National Parks. We spent a night in a cave at Bryce Canyon in 30 deg temps and Alltrails was useless since I did not d/l the map before we left.
