Question: Does any body know what I have to check if my app freezes? I mean, I can see the app in the iPad screen but no buttons respond. I have tried debugging the code when I click on the button, but I haven't seen anything yet. I was reading about the Instruments tools; specifically how do I use them?

Can anybody help me? I just need an explanation about how use the tools.

Answer: 
Besides pausing and following the stacktrace I think as an additional thing to do, is to check in the code if there's any loop causing the app freezes. 

I recently ran into a similar problem, but stack trace didn't help much, I figured out that I was having an eternal loop when calling a `reloadData()` inside layoutsubviews method and that was causing a freeze with no errors and no help from instruments.
The same Issue Happened to me with ios 13.4 and then I tried the above solution but it doesn't solve it. so I had one element with break constraint on the storyboard. So after resolving the constraint it solve the problem.