A few month ago I submitted one of my games to Steam Store, only available for Windows platform, but now I wan to create the build for MacOS too. So, I would like to ask you some questions regarding to this.
Do I have to pay another $100 to submit the MacOS version of my previously Windows version game?
Are more copies sold on MacOS than on the Windows platform?
I haven’t published on Steam, but the Steam Direct Fee is per game, so I highly doubt you’d have to pay it multiple times for a cross-platform game. If you create a separate store entry for it, then you’d need to pay it again.
As for the number of copies being sold on Mac vs Windows, that’s a hard no.
https://store.steampowered.com/hwsurvey/
Steam user breakdown by OS:
We had published a couple of our games on Windows and Mac through steam-- you only need to pay for a single app and you can distribute across all available platforms.
The last build we had submitted for MacOS was back in 2020 so I’m not current with regards any new policies or other changes but it was pretty straightforward.
You need a developer ID provisioning profile through your apple developer account to distribute via channels that are not the App Store and you need to get your builds notarised by Apple-- we used a tool called SDNotary while provides a neat little interface to handle notarisation if you don’t want to do it manually through the terminal