Found this great guide to performing some basic web tasks such as submitting forms, uploading files, and interacting with RESTful services.
In the tutorial Matt goes through using the Cocoa libraries to perform basic web tasks, and also talks a little bit about the excellent ASIHTTPrequest library. He also goes through some principles that you will want to follow when creating RESTful web services. This is a great read on the absolute basics of interacting with the web using Cocoa.
One of the things that makes the Objective-C language “different” from most other object oriented programming languages is that there is no simple command that allows you to print the subclasses of a class. I noticed this early on when using the language, and had to work around this. I don’t know why Objective-C doesn’t have a simple command for doing this (to be honest I never thought about it until this moment), but recently I saw an article on exactly this, and found a few ways to print out those subclasses.
I’m often asked how I keep up with all the new API’s available for an iPhone developer at each OS patch, and really the secret is just keeping up with some blogs. I use Google Reader, place the blogs in there, and skim over them. There’s alot of great blogs out there, these are the 10 that I currently keep in my Google Reader. You’ll go nuts trying to keep up with everything, I tried for awhile, but now I find I can get up to speed just with these resources.
In the course of your iPhone Objective-C programming you will likely have the need for an NSTimer at some point so it’s good to have an understanding of how they work.
I found this good example here on timers: NSTimer the Poor Man’s Threading Code Snapshot
While it’s foolishly titled a Poor Man’s Threading which may give you the impression that timer and thread are synonymous it shows a nice flashy example of NSTimer’s in action. If you’re looking for the Cocoa threading class you will want to look up NSThread which I will be featuring in an upcoming tutorial.
A fun Online Cocoa/Objective-C quiz for beginners has been put up by Olver Drobnik.
The quiz is called "Are you a Cocoa Crack?" and provides a surprising challenging test for Cocoa programmers. I think it’s a fun little test because it’s very short, and easy, but tests beginners on a few concepts that are easily overlooked.