I really enjoy the planning, so once I know our rough route, I research heavily in the tourist sites with google, and also have created a spreadsheet over several years broken down by state/province and closest town I've added info to I've gleaned from other RVer's trips. I also then look at Freecampsites.net, Campendium, The Dyrt, Ioverlander, RVParky and Allstays. I will also check Reviews from others before committing to any specific location.
For the actual route planning I solely use google maps. I've tried all the othesr such as Freetrips, Furkot etc but have found google maps and being able to see satellite earth views zooming in to access parking/road conditions etc, this has been best for our use.
Depending on what style of camping/rving you end up enjoying, we also use Sanidumps when the RV needs to go and we're boondocking for a long time.
Lastly because we like being at one with nature a lot, we will use MUV Maps, BLM, AZ Trust Lands, Wildlife Refuges, Crownland in Canada.
We typically just use on the spot visuals when gas filling (36ft MH) as needed, Finding many of the large Travel Centres are easy in and out.
Many like Truckers Map/Truck Atlas, weather station, and also there's a deep discount fuel card for diesel TDSR? Sorry we are not diesel but gas I'm sure someone else will confirm that one for you.
There's quite an arsenal for you to consider, and you will find over time your favourite go to apps.
Happy and Safe Travels.
It Takes No More Effort To Aim High Than To Aim Low - Reach For The Stars