Apple has released an iBooks version of its iOS Human Interface Guidelines, which is free to download. This document used to be available only to developers, is now accessible to the general public.
But, why? While there are certainly many people interested in knowing the details of Apple’s interface recommendations (and rules), it’s not very useful if you’re not developing apps. Granted, it can be helpful to journalists and tech writers, to find specific terminology, but otherwise, it’s not a document for the general public.
In any case, if you’re interested in checking it out, grab it here.
And, just as a note to iOS developers, here’s a useful recommendation from the book:
Ensure legibility by using the system fonts. iOS 7 system fonts automatically adjust letter spacing and line height so that text is easy to read and looks great at every size. Whether you use system or custom fonts, be sure to adopt Dynamic Type so your app can respond when the user chooses a different text size.
Those developers who insist on using 6-point fonts, because they can read the text at that size, need to think about how many of their users can’t read such tiny glyphs.