I have a newer iPad and an older iPad2. My app is written in Swift and compiled for 9.3.5, which is the OS installed on the older iPad2. ***My app runs fine in the simulator and on the newer iPad.*** On the older iPad2, a lot of mundane things work in the app, but it crashes with errors that are only semi-repeatable when I ask it to do its real work. The problem seems to have something to do with an object being garbage collected before it should be, but I am not sure that is really the problem, as the debugger sometimes gives other death messages that are completely different. Any ideas on this?

I am using UITextFieldDelegate.textField(_,shouldChangeCharactersin,replacementString) in my ViewController. I receive the correct input from my app's software keyboard. But the hardware keyboards on my iPad and my simulator both deliver uppercase characters only to my app. This won't do. Yes, I have checked the keyboards' CapsLock state. Suggestions?