Calculate values in a collection

Hello. I’m Christophe. I’m building a nice app but I’m stuck. I’ve been looking everywhere the answer before asking for your help here. I have two use cases that I can’t figure out how to do with Adalo.The first one, let’s say that a form allows the user to select two digits, like 2 and 3, is it possible to have a third field in the collection where the sum is calculated (2+3=5)? The second one, let’s say that a first collection hosts a date and that I want to calculate the gap between this date and a date of a second collection, and save the result in the second collection. Is it possible? So far, I’ve been able to make those calculations with the custom formula feature, but the result is on a screen, not in a collection. Hope someone can help me, otherwise I’ll have to give up Adalo. Saving results in a database is crucial for me. Many thanks in advance for your help. Christophe.