Not sure where else to post this, so I will do so here.
The Arkham Horror toolkit is a pretty good app. Maybe a bit pricey for buying all the expansion content, but that is not a big deal.
I know that the setup and rules can be varied based on number of players in the game.
I propose that the next time the app is updated, you include a flexible copy of the rules and setup steps. Let the user specify a number of players and maybe even which Heralds and Guardians are in play. Then generate the appropriate setup and turn sequences. Also have a quick reference tab for things like the monster limit in the outskirts, and gate limit.