To record points and tracks? I like Gaia. It seem to be the easiest to set up and get going. At least for the iphone, it is fairly accurate when compared to my Garmin 78 series with externally mounted antenna.
Because I want to stick with Windows (on my Surface tablet) I use SAS.Planet. You need to be a bit of a hacker to get this free Russian software working, but it allows you to download maps from any web source and bring them with you offline for your trip. I have OpenStreetMaps, CalTopo USGS Topographic, Bing Satellite downloaded - and many others.
Avenza. It’s free, has free USGS maps, and it’s what the Forest Service uses for their maps (like MVUMs - also free). There are maps available that you can pay for too. iPad in the truck, iPhone for hikes.
Another vote for Gaia - I like the fact I can plan it on my PC and the route shows up on my iPhone, Android tablet, and iPad. I can also do the reverse of that - track my route on my phone then look at it or share it from my PC when I'm back home. Plus the historical layer is really cool.
It can be free without offline maps. I actually like it so much I paid for the 5-year pro subscription so I can get more map layers (like Nat Geo trails). This has everything I need and more. I use it just about every day.
Gaia is the best, it helps you find a campsite on the road, or deep in the backcountry. It delivers public land data to help you stay legal, maps with campsites, parks, and forests, as well as weather overlays.