Debugging with xcode-8
https://www.raywenderlich.com/152276/intermediate-debugging-xcode-8

You can find pdf version of the page below
Intermediate Debugging with Xcode 8

Adaptive layout tutorial

https://www.raywenderlich.com/162311/adaptive-layout-tutorial-ios-11-getting-started

You can find pdf version of the page and necessary attachments below
Adaptive Layout Tutorial in iOS 11: Getting Started
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xcode project

IOS Visual format language

https://developer.apple.com/library/content/documentation/UserExperience/Conceptual/AutolayoutPG/VisualFormatLanguage.html

https://code.tutsplus.com/tutorials/introduction-to-the-visual-format-language–cms-22715

You can find pdf version of the page below

Introduction to the Visual Format Language

Real-Time Communication with Streams Tutorial for iOS

How To: Pass Data Between View Controllers In Swift (Extended)

How to Use Xcode Targets to Manage Development and Production Builds

How to Use Xcode Targets to Manage Development and Production Builds

Closures
https://medium.com/@abhimuralidharan/functional-swift-all-about-closures-310bc8af31dd