I would like to know what the performance is like of IOS 9 on the Air 2. I currently have an Air 2 that I bought the other day and it has 8.1.2 on it. Right now everything is smooth and no lag at all. Does iOS 9 lag on the Air 2 like it does on my iPhone 5s? If it doesn't lag should I upgrade to it? I don't want to upgrade and have performance issues with lag.