Hello,I used to develop apps several years ago and then stopped. I want to start again but want to develop apps for older iPhone and iPad devices specifically for seniors. Most senior centers have older devices as they are typically donated. I downloaded Xcode 11.4.1 and quickly found that projects created are not backward compatible with the older devices. I then found some of my older code (built for iOS 5.x) and found that with some modification it would start up, but had many issues and would crash in the end.Is there any way to reliably create code that will run on older and newer devices? Or should I write two sets of programs, one for iOS 9.x up to 10.x or 13.x (becasue that seems to be when many things changed) and then another for devices on newer versions of iOS?Thank you for your help!