WWDC Videos
What's new in Camera Capture (iOS 6)
What's new in Camera Capture (iOS 7)
Camera Capture Manual Controls (iOS 8)
Advances in iOS Photography (iOS 10)
Rendering a screen covering triangle https://rauwendaal.net/2014/06/14/rendering-a-screen-covering-triangle-in-opengl/
Great introduction to Metal https://www.objc.io/issues/18-games/metal/
Getting started with shaders https://gamedevelopment.tutsplus.com/tutorials/a-beginners-guide-to-coding-graphics-shaders--cms-23313 http://www.shaderific.com/glsl-functions/
Shader Toy https://www.shadertoy.com/results?query=tag%3Dpostprocessing
Working on the macOS target https://www.objc.io/issues/14-mac/appkit-for-uikit-developers/