And as we all know already, iOS 9.0.2 dropped.
This one actually downloaded wirelessly for me, outside of the house, sitting on the patio, no issues. It was a small bug fix. Did notice a couple of times the built in calendar app and even the main screen would become unresponsive to touch on my aging iPhone 4S. It did however let me force close the finicky app.
After a reboot of the phone, no more issues. Of course I'm probably pushing my luck running iOS 9.0.2 on an iPhone 4S just the same though. I suspect the same results with the old iPad 2 too. (Tutu?)
October 1st update: I find the 4S starting to get more erratic under iOS 9.0.2 the more I use it daily. I think it's "matched it's meet" or met it's match in future iOS updates. A faster fone (<---spelled that way on purpose) is in my future I think.