Apparently it's not only Simcity but I have the same problem on other apps and games since iOS 9. It's only happening on my iPad Mini though, not on my iPhone 6 Plus which works perfectly.
I have also noticed that the system overall gets serious freezes (still on iPad Mini) at any moment: this goes from pin start screen to any other app. Touching the screen just produces no result at all, and after sometimes up to 5-7 seconds the situation unfreezes... It is really frustrating.
