Since I'm using a third party component for In-App Purchasing, I'm not sure where this bug is, but it seems that SKRequest.start crashes when there is no connectivity to the Internet in general (or to the AppStore in particular).
My solution is to check for reachability to the AppStore, because that's what we really care about. I'm using Indy for a multi-platform solution (as opposed to iOS APIs).
I offer the following code up as a solution. Tear it apart... ;)
uses
..., IdComponen...