The current answer
Download the map and the language pack before you leave the wifi. Check the download actually completed, because a partial one looks identical until you need the missing part.
This page is still being built. Until it is complete, verify independently using the sources below. The method in the book does not change; the specifics do.
Where to verify it yourself
- Application documentation for offline coverage
- Independent reviews from mapping communities
What the book says
See Phase 6 §1. The book teaches the method for working this out. This page carries whatever the current specifics happen to be.
What changed and when
No revisions yet.