This is Larry from Brewer's Friend. Our next release of the iPhone app will handle brew session and brew log sync, and it is currently in the app store awaiting review. It will be out any day now. The iPhone app does run at 2x on the iPad and is a good solution if you don't have wifi in your brewing area.
I'd be curious to know what aspects of the online experience 'while brewing' are not working for you? Also what feedback do you have for the iPhone app (aside from the fact it is indeed not native to the iPad)? It is possible I can point you to the FAQs or help iron something out that is already supported, or possible there is a simple feature we could add that would make life easier. We want to know!