[josv]

We don’t lack for wonderful writers in the Apple ecosystem. Along with objc.io I’d heartily suggest:

https://oleb.net (Ole Begemann) https://www.mikeash.com/pyblog/ (Mike Ash)

[wool_gather]

Can't beat Mike Ash. His Friday Q&A series is just fantastic: plenty of people tell you about what to do, others will explain the why, but read those and you'll get the what behind the why, and why it is that way.