iPhone 4s iOS 9 Update: 10 Things to Know After Three Weeks

You Can (And Maybe Should) Try the iOS 9.1 Beta

If you want to, you can try the iOS 9.1 beta right now. It's free and it should be very easy to switch from the beta to the public release when it arrives. If you're interested, take a look at our list of instructions. They will help. 

Just remember, you can't downgrade to the iOS 8 update so if you do make the move, you'll be stuck on iOS 9 going forward.