About the cloth / way of cleaning the NANO screen and regular iPADs (opens in new tab)

I have been using the IPP 10.5 with the naked screen, and since 2017 also a microfiber cloth for electronics, mixed with tap water. The screen doesn't look in any way damaged or scratched. I have doubts about the pre-OLED iPADs and this new 1 TB NANO screen. One user here said: I wonder how...