The thread title is very self-explanatory already, so I can;t explain much further. But just to add more details, I need the information because I'm making a campaign that uses multiple maps, so I need this to go on.
Varine is probably right, but if you got a campaign that's more than 20 - 30 maps, then I'm betting you'll have sections you could probably divide the campaign up into, in which case you could create a separate campaign for each section
The usual of the Blizzards campaign is around 12 missions, I believe you can have as many as you can but people would rather have it cut in 10-12 missions a campaign, like Varine said
I'm currently creating (as a hobby) a space invaders like game for mobile using Xamarin, after starting a few larger projects that I also may not have finished
Awesome! you should look at the Atari VCS platform it does not have a huge user base but the one it has is super active at around 11k and they have no games in there store