It's all fun and games until the iPad stops working, particularly for those that are relying on it for their position, which I believe is many pilots even though they are not approved for this purpose.
I happen to know that a GNS 430 will happily run all day without the fan running. It's my understanding that this is a requirement for certification. The chassis will become as hot as hell and you'll almost burn your leg of it leans against it, but it won't stop. It's one of the reasons why TSO'ed costs so much...