In reply to TheDrunkenBakers:
I guess it depends on how off-grid you are and how much detail you need?
I use Google Maps for rough planning. The mobile app can store local maps in most locations.
I usually create walking locations between a couple of points on the desktop app, then drag waypoints around to make a loop or make the route more specific to what I want. Turn on the terrain layer and you get an idea of hilliness. The route directions will even show you elevation.
You can then send this to the Google Maps app on your mobile.
I use Trace de Trail for detailed planning and creating printable maps. It's French but has lots of international map layers you can use. However I've found the hard way that the app isn't the best when stuck up a mountain with no mobile signal (caching the map etc).