I reviewed the low cost (free to try) Osmand app. It downloads and stores regional Open Street Maps, so it doesn't need a cell signal.
My review post is here.

I saved a route file from ridewithgps.com onto my android tablet. (I think I used a .gpx Track file.) As I remember, it was a little confusing to figure out at first, so try this well in advance. But the track worked fine, showing as a colored line on the map.

The Galaxy S5 is waterproof and sweatproof. I keep mine in my back jersey pocket with no protection. Very convenient.

But the charging port is not waterproof. And I don't think the screen is very visible in bright sunlight. Those would be the two downsides to using this on the bike.