Nameless Range
Well-known member
Google Caltopo. You have the capability in that mapping program to build custom geo-referenced PDFs using imagery/topo/USGS background and you can mark up the maps however you want them. Then you just email them to your phone and import it into Avenza.
Caltopo is awesome. I'd add that any ArcGIS Online webmap/app that has a print widget will print out a georeferenced PDF. Fire fighters will spin up a map in CalTopo or some publicly available web app and be using that map via a mobile device on the fireline in minutes. All it takes is one person with connectivity, and then they can airdrop the PDF to everyone else.
There's a reason the USFS and others utilize Avenza for operations. There are no bugs, it's simple, and it always works.