Is there a way to track when a xamarin.forms app shuts down

Hi I am trying to implement a rollback functionality for my xamarin.forms app. Basically I want to execute some code that would run when my xamarin.forms app is interrupted due to a crash or abrupt shut down of phone, etc.

I found couple of links and one of them here mentioned about Activity.onDestroy() but activity refers to a single activity as oppose to the whole app so it is triggered only when that activity is destroyed and not equivalent to the whole app shutting down. I was wondering if there is some sort of xamarin.forms extension to determine an app's abrupt shut down.