Android Apps for RV'ers

Just wondering of any useful android app for rving? I'v been using

this one https://play.google.com/store/apps/details?id=my.travelcheap.rvdiscount to match up goodsam and passport parks

And this one to find other park and places

https://play.google.com/store/apps/details?id=com.rvparky.android2

And this one to find walmarts that let you park overnight

https://play.google.com/store/apps/details?id=my.walmart.overnightparking.abcdefinder


I do like the free apps better the paid lol...