RPGScenery is a bit of an oddity: a map editor without the ability to edit maps. But it certainly looks gorgeous - and has huge DLC potential. :)
https://store.steampowered.com/app/1689510/RPGScenery/
Another Steam Weekly deal - Portrait Wizard for 25% off:
https://store.steampowered.com/app/685300/Portrait_Wizard/
It's worth noting that this is Early Access software.
The character generator for an upcoming CRPG Spire of Sorcery could be useful for a TTRPG GM as well, IMHO:
https://store.steampowered.com/app/893560/Spire_of_Sorcery__Character_Generator/
Ever wanted to see who bonded with whom? Who are the outsiders in your campaign? Who are the key persons?
I started experimenting with a visualization of character relations. You can find the current result here:
https://minor-level-7863.roast.io/ (it's free hosting, so no guarantees for...