I want to set a cell to a default value as soon as a form is submitted to a spreadsheet (I want to add a value after the last value from that the spreadsheet gives me). Since upon a form submit it erases all the values in the row, I can't have a formula in this cell, I think I'd have to do it with AppScripts. I tried doing it with onFormSubmit but I did not get very far with it. Is there a way to do this?