Offline maps are the way to go. I made a habit of having all of the US always stored in my phone just in case something bad happened. Only takes 12GB or so. Cell service can be spotty in large parts of the country so you can’t depend on Internet maps.
Then it paid off. Plane lost an engine mid-flight, had to emergency land 850 miles from where I needed to be, and off I went by rental car with map in hand…er…cupholder.