When should you use recursion $($instead of iteration$)?$

Only after a standardized timing test has been executed and the results favor a recursive solution

Only when it's one of the following problems $($or a problem that can be mapped to one of these problems$)$:

Factorial

GCD

Fibonacci Numbers

Binary Search

Towers of Hanoi

There's a straight forward recursive solution $//($or it's the only solution$)$