I bought an iPad for lots of different reasons. Shortly after, my boy claimed my laptop. It's all good, since this does everything I did with that and is a lot more fun.
I found a recipe app called Paprika. It's perfect for what I need. The ingredients list is what you type in, not a pre-defined setup that really doesn't fit how I do things. The procedure section is the same. It has a good selection of pre-typed words, such as measurements. There are no included recipes, but I have all the ones I want to put in. It has a built in browser and can import recipes from supported web sites. I tried with SMF, but it's not supported, yet. I asked that it be supported, but haven't heard back yet.
One of the really cool things with Paprika is I added a folder for 'how to' things. For example, I added one for using the minion method for charcoal, Listed the 'recipe' which is charcoal, chimney, etc., and in the procedure section, explained the process. This will work wonders for working with Scouts.
Even as I type this, the iPad is secure from spills and other messes firmly inside a gallon size ziploc bag.
Granted, using it only for this would be silly. But, I also have games to play while the food is cooking, can check my email, the weather, etc. About the only thing it can't do is get me another beer. Maybe someone will write an app for that....