Previously available on the web from Apple’s developer portal, the company’s iOS Human Interface Guidelines are now on the iBooks Store as a free download (via Dave Addey). The 20 MB guide is compatible with iPads as well as Macs running iBooks on OS X Mavericks, and it takes advantage of the app with inline video playback, two-page page layouts, and built-in annotations (plus, of course, font size and color controls for reading settings).

It looks like Apple did a nice job in converting the guidelines to iBooks, and annotations appear to be especially useful for developers and designers learning the principles of the iOS 7 visual language. The iOS Human Interface Guidelines are available on the iBooks Store here.