If you are a Good Sam member you may take a look at their trip planner. I don't know if it will work on a smartphone rather that a desktop or laptop. It will let you alter your route to your liking to see different attractions or landmarks. The campground feature is a little limited as the planner does not give you all the campgrounds that are available. It likes state parks and Good Sam campgrounds and selected private campgrounds, but it will give you warnings for low clearances if necessary. Let's you plan your travel each day and gives you very detailed driving instructions, sometimes a little more than you need, but gives you mileage on the route (sometimes not quite accurate but close enough).
I like travel off of the interstate to see more scenery and slower pace of travel, plus fewer billboards to block my view. Some trip planners won't let you pick and chose the roads you may want to travel. The Good Sam trip planner will let you change your route which is a feature I like. I used it twice for travel from Atlanta to Houston, a slightly different route each time and a couple trips to central Florida, again a different route each time.
You might just Google "RV trip planner" or "RV trip planner apps", lots of choices to pick from. All depends if you want free ones or subscriptions. Most will give you a demonstration to look at.
2014 Palomino Puma 25RS
2011 F-150 Super Crew XLT
Days camped in 2014 - 23
Camped 2015 - 47
Camped 2016 - 51 done - 6 more planned so far