iOS is smooth, elegant, and easy for users. The system just feels more solid and reliable than alternatives, such as Android.
Apple's takes Microsoft's place as leader in frustration for developers and, in true Apple fashion, charges the developer for even the most minimal usage. Unlike Google's app store, which allows developers to post their apps for free, Apple charges $99 per year for developer services such as the iOS store. Many iOS developers never profit from their apps enough to even pay back the $99 fee. It gets worse - Apple takes a 30% cut of all revenue, whether from app sales or in-app purchases.
While the financial details are upsetting, what I take issue with most is Apple's disinterest in making iOS a decent environment for web/cross-platform developers. Just as Microsoft in the days of "old IE", Apple's browser technology support is generally stagnant. In my most recent project, I encountered a hardly explainable bug and had to rework a lot of my logic to work for iOS, as it lacks webm video and WebRTC support, though, this complaint is only scratching the surface of what Apple is lacking that other vendors have implemented. Another huge frustration, especially considering the $99 yearly fee, is that Apple's application build tool, Xcode, is only available on Mac computers, so ubuntu developers have to switch machines to compile their apps for iOS.
My last major complaint is with the app publishing process. Apple requires that submitted applications be reviewed by their staff before being made live on the iOS store. This process generally takes a week. If a major bug is discovered, even in the best case scenario that the bug is fixed and a new version is submitted that day, the application could be in an unusable state for a week waiting on the Apple review. While we hope there would not be any such devastating bug, it is very unsettling to consider the possibility.
If I were able to publish for Android rather than iOS, I would choose Android, hands down.