I recently read this terrific article in the New Yorker about cookbooks, and I think one of the reasons I liked it so much is that it hits pretty close to home -- I do like reading and browsing cookbooks, and I don't cook nearly as much as I want to. And I can totally identify with the tension between searching the pages of recipes looking for a secret, weighed against actually getting the experience necessary to be a great chef. From the article: "The recipe is to spend your life cooking."
But that hasn't stopped cookbook writers from trying to import as much knowledge as they can. The Ratio cookbook is one that caught my eye recently; rather than giving out recipes and directions, the book sticks with math and recipes as a way of breaking down foods and the way they're made. Instead of step one, step two, step three, it's one part sugar, two parts fat, three parts flour, mixed up and baked. It's an interesting way at examining cooking, and now it's come to the iPhone -- the cookbook (or at least the ratios and recipes from it) is being released as an iPhone app. You can browse the "32 critical ratios" for doughs, meats, and sauces, a unit converter, and other recipes including ways to share and tweak your own. You'll probably need to know a little about cooking already (and as that article says, just knowing the recipes doesn't actually give you the meals), but it should be a helpful reference.
All the page says is soon (no price yet, either), but if you keep an eye on Michael Ruhlman's website, they'll probably post when the app is out in the store.