If you have started working on WatchKit apps , David has a nice blog to help you out with basic stuff. This one helps you with displaying tabular data.
If you are into building universal app to save time and avoid duplicated code this post is for you. Based on this experience building apps Justin has written this brilliant post with an example custom view code.
If you haven't been following official Swift blog, you should! This post shows you one way how you can use REPL while developing apps.
If you are working with a reasonable amount of data inside of arrays in Swift, you should read this post. David investigates why the rendering code he had written was slow in Swift as compared to Objective-C and in the process shows how to debug such issues.
There are many things we need to make sure of before submitting our app on iTunes connect. Folks at Stanfy created a handy checklist in this post for us so we don't miss anything.
David writes about how he designed his WatchKit app to accompany his podcast and audio book app.
Things have changed a lot recently with Sketch, the design tool. If you use it, Timur has written this post to show his latest workflow with Sketch.
Android 19.1 support library introduced annotations. If you don't know about them or wondering how to use them, Anup has written this post for you.
How Facebook made it's news feed faster by implementing a new architecture.
This is a post on how to use Android studio to its fullest by integrating Gradle and testing frameworks with it.
Design co-founder at Feedly redesigns Feedly app with Material Design. Arthur takes few material design principles and applies them to Feedly app. Highly recommend reading this.
Nice writeup on how Paul went about design icon for their Android app.