If someone can show me any proof of certification of an iPad as aircraft equipment great
I can assure you that Airbus (and presumably Boeing) test iPads in a number of areas from decompression to cold temperatures and also for RF interference. It is in a document for each iPad model and is available for purchase and used to show the NAA that the iPad is approved model. I can't send you ours as it cost my company money.... It can be argued that it is part of the aircraft equipment when it is a no go item on an MEL. In the US with at least one operator, that day is here.
As an observation, there are a few people here going to be rather surprised when they find their Airbus QRH on the iPad before the year is out.