I agree with <tomnipotent> about being able to update the server independently of the app. That's a good reason right there (the app requires network connectivi

I agree with <tomnipotent> about being able to update the server independently of the app. That's a good reason right there (the app requires network connectivity for email, after all). Another reason is specific to this use: Amazon distributes a Linux command line tool called KindleGen that converts HTML to .mobi formats. You could install KindleGen on a Linode box in seconds and have a proof-of-concept converter running in hours. I suppose you could reimplement KindleGen yourself for iOS if you had unlimited free time, but it likely wasn't worth it for this particular project. Just look at the release notes for a single version of KindleGen: -) Enabled support for JP vertical rendering and multiple page writing modes (L to R, R to L) -) Enabled support for facing pages (left or right) -) Enabled support for double page spreads -) Enabled properties to support spine for fixed format content -) Added KF8 and M7 file size stats that will be displayed after conversion -) Added Mobi7 support for HTML tags with multiple classes (e.g., class="class1 class2 class3") -) Data URI support for images and embedded fonts so that they can be referred directly in HTML and CSS files -) Multiple bug fixes and enhancements. And remember the author of the linked article wrote that the purpose of the app was to "experiment with various revenue models on the App Store..."