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From the iOS Apprentice Series. As I found so many best practice information in this (paid) book, I decided to go through the entire series though a lot of stuff is intended for complete programming beginners.
A mini game. Contains everything needed to get up and running w/ iOS development w/ Swift. Can't remember to have read any programming tutorial as both funny and useful as this one. Many good laughs.
To-do app. Introduces UITableView and UINavigationController, MVC, data models. Very tense. And still easy to read, humorous, witty - a didactid masterpiece.
From the AutoLayout video course ( http://www.raywenderlich.com/video-tutorials#autolayout - subscribers only...)
From the excellent Core Graphics tutorial from http://www.raywenderlich.com/90690/modern-core-graphics-with-swift-part-1 - You might have noticed that Apple's Health App's graph view is reconstructed there?
From a Ray-Wenderlich-the-master-himself course on CALayers ( http://www.raywenderlich.com/?p=107229 - subscribers only...)
From a Mikael Konutgan tutorial ( http://www.raywenderlich.com/82058/custom-control-tutorial-ios-swift-reusable-knob - freely available) on creating custom controls.
From a storyboards tutorial by Caroline Begbie.
Different playgrounds
From a Sam Davies tutorial ( http://www.raywenderlich.com/video-tutorials#stackviews - subscribers only...) on - yes! - Stack Views.