Key-value observing seems to be the weakest link in the Cocoa library. Soroush has a list of pitfalls to avoid while using it and the scenarios in which it's fine to use. Also worth reading is the write-up from Mattt Thompson - http://nshipster.com/key-value-observing/
It drives me crazy everytime I have to find the correct syntax for regular expression in the editor I am using. Here is the Xcode version.
Eliot Fowler presents this clever code for implementing circular sliders into your iOS apps and the instructions to optimize it.
Sometimes the only refuge we have is the iOS documentation. This is a great post mortem by Fille on a bug he found in SpriteKit after referring the documentation. Proves that we are not always wrong :)
If you were a web designer before you can completely relate to the inability to easily implement your designs in mobile apps. It's not as easy as HTML and CSS but Meng being a designer himself has done a great job to make it easy for you to implement your own designs.
Blog post by Julius Tarng about the process he took as a designer assisting the engineers with the coding and layout of the UI in his app, Potluck.
A designer and developer have worked together to make it easy for app designers to add design by features demonstrating limited code correction.
Designers and developers created this resource that provides over 24,000 icons to add to apps. Not a bad time to look into their Christmas category, right?
You probably heard this through interwebs - Chrome apps are coming to Android! Great to see Google stepping up and allowing developers to harness the power of both web and mobile, ultimately making it a win for developers.
Some fresh perspective on an age-old question.
An introspective and rather charming tale of the beginnings of an app developer getting his foot in the door of the mobile industry.
Need a timer within your app? The folks over at Java Experience have added a handy guide to adding it from the Android API using the Layout file and Java.
Much like the iOS cheat sheets we linked before, this Android version by Petr Nohejl is a great tool for designers to keep on tab for their work.
Insightful post about the user's physical connection to their devices and statistics behind them.