In reply to ChrisJD:
There's also a free (as in beer and as in speech) version if you use Android since OsmAnd is open source.
You can get OsmAnd~ from the F-Droid store which has most osmand+ features unlocked.
(But consider paying for the app if you get good use out of it. Unfortunately the developers don't provide alternative methods of donating so if you want to avoid Google there is no way... )