Each route takes into account the type of RV you're driving, set in RV Tools, RV Info. Rand uses its many years of routing expertise and proprietary map and vehicle restriction data to set the route based on these parameters. To fine tune the route calculations, you can also adjust the settings under Preferences, Route.
You can manually alter the route by adding a via point. To add a via point between your origin and the destination, select the location by tapping on the map and then tapping the Add as Via button. Or enter the location under Choose Destination. On the confirmation screen, tap Add as Via. The route will take you to the via point and continue on to the destination after you've reached it. By tapping on the map, you can also detour around that spot (if it's on the route) or add it to the permanent avoid list (if it's not on the route).
At any time while you're navigating a route, you can also tap the "cog" button in the lower left hand corner to detour by distance or road segment, or to cancel a route. Tap Detour and select the number of miles on the route to be avoided on the left side, or select a particular road to be avoided on the right side. You can also detour from the turn-by-turn directions list on the right side of the map screen. Tap any road name or maneuver to detour around it.