Useful for last minute plans
Stumbled upon this app when searching for a campsite, and my friends and I were able to book a trip to Yosemite because this app found us a cancellation, which helped so much because we were almost unable to go! Overall positive experience using the app!
Ultra fast campsite Finder
This app gave me a free credit which I used to book a really hard to get campsite in California. I recommend giving it a try. It has some cool features like the ability to search for 8 specific dates, and the prices are low.