I was about to comment on this. Does this game really needs camera rotation? I think, it does not, unless you have some really complex vertical landscapes on mind, like tall walls and hills. I guess, mobile gameplay can benefit, if you fix the view angle, and leave only zoom to be changable.
Since it’s will be still in 3D and you probably want to show your assets better, you can change camera pitch with the zoom like in some games, low camera - lower camera angle, far camera - steep angle, giving more tactical view. You can also add cinematic cameras on attacks, and while it’s enemy turn.[/quote]
I do agree that rotating camera is questionable if its a good or bad thing, but at least I have learned to use it after fiddling with it. Maybe it can turn people away from the game, if it ever gets finished, but it is not like I think the game would even ever be popular to begin with. I just figured out to make a game that I would like and have a scope that is somewhat doable. But yes having a fixed angle camera might be better overall or fixed step turns such as 22.5 degrees turn per press of a button, although that would add more stuff on the UI, which I would prefer to be as minimalistic as possible.
Actually the rotating of camera came to exist by accident. I was testing out unity, when the unity5 came out, and tried to make the bare bones of the game with unity to see if it would be any easier/faster/see the performance on unity. So I made the camera controller for mouse and made it move around with right mouse button and by default I think Unitys behavior for android for the right mouse button is actually having 2 touches. So when I tested it on my phone, i noticed that i can rotate the camera around when holding 2 fingers at the same time. So I figured if people can associate 2 finger movement with same as using mouse right button, which seems to be the way Unity does things, I decided to make the camera work the similar way on my game.
Then to get rid of the slider, I wanted to try implementing camera distance and pitch into same rotation. It is an assumption that if people want more of an overview of the situation they would prefer to zoom out when watching down from the sky, so it is bit of experimental thing atm.
I also noticed that this game seems to use something similar for their camera with the exception of having pinch as zooming, which I thought to try out couple of times, but never did. [video]https://www.youtube.com/watch?v=vecJydg-2L0[/video]