https://numbergamer8.itch.io/sheetsanddots

this app has 100 map zones you can place icons on maps, locations , rooms, char sheets,

its simple way to organise a big set of areas (100) and have icons for PC & NPCs , many thousands items, you can have a main map, then each building, then each room all in the same app with placable items. you can place numbers etc...

the app was made for a space game, but its a shell for an RPG, its free for PC