In preparation for this road trip, I had joined a number of RV "clubs" and downloaded a number of iPhone apps. Some were very useful, some less so.
Good Sam's Club: This is one that I've used on just about every RV trip over the last 25+ years. It gets you 10% off on the daily campsite fee at participating campgrounds, a 10% discount at Camping World stores, and a discount on diesel at Flying J truck stops. I more than recovered the membership fee on this trip. I used their app to find campgrounds down the road.
Good Sam's Road Assistance: The one tow in Redding,CA, paid for this. I could have called them in Idaho to change the blown trailer tire but figured it would be faster to do it myself. They have an app but I never used it. I just called them on the phone.
Passport America: Another discount campsite club. If you stay at one of their member campgrounds, you get a 50% discount on the daily rate. The discount is usually only for one night. I think we broke even on this as most of the campgrounds don't provide the discount during their peak season. But the membership paid for itself after only being used three times. I used their app to look for member campgrounds and to look at their discount policies.
KOA: We stayed at a couple of KOA campgrounds and received a modest discount. Probably not enough to warrant joining. Their campsites were generally had more amenities suitable for a family such as miniature golf and larger playgrounds. I used their app to look for campgrounds down the road and they usually had space as they generally cost a bit more.
Harvest Host: We stayed at four of their sites. You need to join before getting access to their database. It was worth joining as we enjoyed staying at all four of the location. The locations can be wineries, fruit stands, farms, or museums. Generally, they ask you to visit their site, store or tasting rooms in exchange for the free parking site. Generally, no hookups but one of them had water and electricity. There is no app, just a web site.
AllStays App: This was our go-to app when we needed to find campgrounds, rv parks, rest stops, truck stops, Camping World, Costco, Walmart, BLM sites, etc. It was well worth the $10 and it was used regularly when looking for the next campground or when we needed fuel or food. The app also lists road grades and low bridges.
GasBuddy App: Useful app to compare fuel prices. What the apps don't tell you is how open the parking lot is to maneuver a 33' trailer that is over 13' high.
The last app that I used regularly is LevelMatePro. It works with some hardware mounted to the wall and communicates using low energy bluetooth. It's really convenient to see how level the trailer is side to side from the drivers seat when pulling into a camp site.
Some less than useful apps are Sanidumps+, Roadtrippers. Due to the number of RV parks we stayed at, finding dump stations between RV parks wasn't needed. If we were dry camping more then maybe. Roadtrippers is an app that helps you find things to do while on the road. I never really had the opportunity to try the app out.
Not really an app but one of the "fails" on the trip was the Spot 2. The hardware failed, the company said hmmm, and in the next breath said no refund for the remaining ten months. Basically, too bad. I'll never get another one again…