Somewhat unexpectedly, many designers are now would-be animators too, thanks to the transformation wrought by native mobile apps. Mike Rundle’s new book, “Motion Design for iOS,” the latest installment in his “Design Then Code” series, offers the best yet overview of what it means to bring the magic of movement to what has until very recently been the relatively static art of designing digital products. It’s a how-to book, but it’s also a flag planted in the ground—if it’s not the first, then it’s likely the best yet statement on the intersection of these two disciplines.

“Motion Design for iOS” debuted just this week, and is on sale for US$20 off for a limited time.