CoPilot. At the recommendation of this forum I now use CoPilot. You do not have to have cell service to use the CoPilot app. It does have an RV setting. I still double check the route on the Atlas to be sure it's routing on major highways. No GPS is perfect. I wouldn't follow it blindly.
Vehicle Preferences
You can adjust how your CoPilot calculates routes based on the vehicle you're driving.
From the user guide:
In the Main Menu, tap Route > Vehicle Preferences
Select your vehicle type, choose from Car, RV (Recreational Vehicle), Motorcycle, Bicycle or Walking.
Toll Roads: Choose to Use, Avoid if Possible or Always Avoid toll roads along your route.
This option is not available for bicycles or walking.
Choose to use the Quickest or Shortest route for your trip or use ActiveRoutes* for routing based on actual road speeds at the time of day you're travelling.
Avoid Ferries – Tick the box to Avoid Ferries along your route where possible
Custom Road Speeds – The ultimate in personal route settings. You can choose to favor or avoid specific road types and allocate a personal speed setting for each. For each road type, first set CoPilot to Strongly Avoid, Avoid, stay Neutral, Favor or Strongly Favor certain roads when calculating routes, then set your preferred speed for each one.
This option is not available for bicycles or walking.
Show Walking Breadcrumb - When you're making a journey on foot, CoPilot can guide you from your starting point to your end destination by displaying a dashed line for you to follow. A walking breadcrumb can be displayed in the map to show where you have walked.
This option is only available for walking.
An icon is displayed in the dashboard to show you the mode of travel you've selected.