I currently am a mobile developer on Android. Nonetheless, I am interested in iOS and particularly the Swift programming language, so I try to pickup any related knowledge when I can find a spare moment.
Sean Levin, a Senior iOS developer at Yahoo!, gave a very good talk at the March 2016 Brooklyn Swift Developers Meetup: "The Wacky Wild World of Swift Collection Types". I wasn't able to attend but recently viewed Sean's presentation available online. For me, the value of the talk was his cogent walkthrough of the Swift concepts of a Generator, Sequence, Index, and Collection.
Elements of Programming
Around minute 37 of the presentation, Sean briefly digresses to mention "Elements of Programming" by Stepanov and McJones. I had not heard of the book but was loosely familiar with Alexander Stepanov, being a progenitor of the C++ Standard Template Library (STL). The book sounds dense and mathematical but, at the same time, intriguing.