Foundry VTT, Dungeondraft, whatabou dungeon generator, Mork Borg DUNGEN and monster generators, Procreate for drawing dungeons, Stable Diffusion for images I can’t find, various character generators/builders for whichever game I am running.

not a gm but in a game I play in they use www.owlbear.rodeo and I don’t think it costs anything and is pretty nice. its a play by discord. between that, wanders guide, and the kobold discord add on it pretty much covers everything.

Most useful: pf2easy

Foundry VTT (Hosted by Forge). We play in person but it’s still good. It works well and has super pretty maps, but we only use it as a map, not the advanced features. Also takes a LOT of resources, a shitty tablet or old laptop might not keep up. Not super intuitive and hard to use with a touchpad/touchscreen. I stoll recommend it though :P

My players use Pathbuilder.

Oh and AoN of course, but pf2easy is usually faster.

I haven’t played online yet, and I certainly haven’t GM’d a virtual game. But it’s interesting how the same tools are coming up in both the online and offline posts.