If you’re looking for a web-based flipbook that works great on iOS (and other Flash-less devices), take a look at treesaver.js. It’s an open source script that automatically builds properly formatted pages that swipe great on the iPad and look great, too. Since it’s stock HTML5 and JavaScript, it works great almost everywhere.
Lightweight and fast, the Treesaver.js app doesn’t add any crazy overhead to your content but putting your content into the system and making it look nice still requires quite a large bit of elbow grease. This is due, in large part, to the unfinished documentation on the Wiki.
But, the software is only at version 0.9.2 currently, so there’s plenty of time for the community to help out. I love open source software.