ios objective-c development tutorials

Finally, I started learning about ios development and it's all about objective c learning. here is a collection of tutorials that i find useful. Obviously, the real challenge is to actually do the ios coding so you actually have an iphone app launched in production. Tutorials are everywhere but i find video tutorials particularly useful compared to just reading books. But it's easy to just watch the online videos without actually doing the exercises yourself...

Let's see where it takes me...