Regarding navigation and (online) maps, assuming some data won't be cached locally -- like your planned routes and possible deviations / alternate paths --, you can always use your phone (and some specific app?) to plan your treks.
The problem parallel to that is if you're in the wilderness...
[Preamble: originally I tried to post what follows in r/Rivian, but I got this message: «Sorry, this post was removed by Reddit's spam filters. Reddit's automated bots frequently filter posts it thinks might be spam.». I'm posting this here, but if it still not allowed -- or it's in the wrong...