I often get asked what are the “must-read” books or web sites for an aspiring mobile user experience or user interface designer. There are a bunch out there, but if I could only pick one, specifically for those like me in mobile app design, it would be Apple’s iOS Human Interface Guidelines (with the Android Design web site being a very very close 2nd place).
Apple’s guidelines are free, well written, and offer plenty of universal design principles that apply to other mobile platforms.
What isn’t as well known (or at least not as publicized) is that Apple occasionally updates these guidelines, notably for newly released software such as iOS 6, but also to evolve or expand upon some of its design recommendations.
If you’ve read these guidelines before but not in a long while, I strongly suggest that you take a look at the latest version, and scroll to the very end to read the Document Revision History. Here are a few recent revisions that I found notable:
In general, avoid increasing control sizes (Page 51) / Don’t use the extra space to display an additional bar or banner (Page 51): This was an older-dated revision, related to customizing your user interface for the larger iPhone 5 screen. Still, it reminded me of a bit of personal design advice: When designing screens for an iPhone app, always mock them up based on the smaller 3.5-inch screen to start … not the larger screen! It’ll make sure you don’t have critical design elements getting chopped off anywhere.
Avoid using an image view as a button (Page 141): This made me do a double-take because I’ve done this before in my own apps. While I completely understand the reasoning for it, my response to Apple would be this: If the user won’t know the difference in terms of his or her experience, does the behind-the-scenes implementation really matter? (Maybe it does, if Apple’s planning any big changes to these basic classes in iOS 7 or later).
In general, display only one scroll view at a time (Page 149): While this wasn’t exactly news to me, what I found interesting was Apple’s solution if you must have more than one scroll view. If you need two, “consider allowing them to scroll in different directions so that one gesture is less likely to scroll both views.” Anyway, I thought that was an interesting solution.
If you’re an iOS programmer or designer who’s never read Apple’s iOS HIG before, take the time to do so now. It’ll open your eyes to how and why Apple designs great apps. And if you have read it before, jump down to the Document Revision History and see what’s new.
Finally, if you disagree and think there’s a better “must-read” app design resource out there, let us know in the comments!