It has been almost 6 years since iOS SDK first came out (early 2008, source: wikipedia), and the industry is entering a consolidation stage. From my own experience, last year, iOS developers are widely sought after for enterprise app development, and among digital/marketing agencies. But it has a few caveats:
1) Many new developers, some with web development background, have gained experience on app store, and started working for consulting agencies. This trend drives down the hourly rate for iOS developers;
In the next series, I will talk about the app store. Got this idea from my own experience and this BI article.